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Faerun has a variety of languages, and hundreds of dialects. The following list has been compiled from many sources, some of which have conflicting information.
Languages are in Bold, with dialects of that language listed in bullets.
Haze Rule: With the added complexity of a multitude on languages, every character starts with a number of bonus languages equal to their intelligence bonus over 2.
These languages are often spoken far-and-wide, though they often do not possess the nuance to discuss truly in-depth topics and philosophies.
Common (Faeruni): Faerûn. Written in Thorass. Common is the trade language of Faerûn. Almost every sentient, civilized being speaks a smattering of it, and most are fluent. The people of Faerûn are thus able to converse with each other in this language. Common is little more than a trade language; that is, it is not useful for complicated topics. It is simple and not very expressive as a language.
Speakers. Nearly everyone on the surface of Faerûn speaks Common as a second language, including non-humans. Those in remote areas sometimes speak it badly, but most could get by. Most speakers will try their native regional language first. If they are not able to communicate in that way, most switch to Common. Using Common is a good way to say, "I'm not from around here."
Kara-turan. (Trade Tongue): Kara-Tur. A common language devised long ago to facilitate trade among the peoples of Kara-Tur.
Midani. Zakhara. The common language of the southern lands of Zakhara. Midani is influenced by the elemental languages of Auran, Aquan, Ignan, and Terran due to the influence of the genies in Zakhara.
Aklo (Undercommon): Also known as Deep Speech. Underdark. Written in Espruar.
In addition to Common, every character knows the regional human language of their homeland. Most people communicate using their regional language first, and then if there's no understanding, switch to common (Faeruni). Only the most isolated of places would not know their regional language, although there are races and cultures that don't have an understanding of Common.
Dialects. The primary languages listed below each include a number of dialects. In official sources, many of these dialects are listed as languages in their own right, but in the Tales of Faerun campaign, these languages are considered dialects of larger, regional language families. Characters speaking different dialects can still communicate with one another, but there are phrases, vocabulary, and wording choices that make them sound different. Communicating with someone who speaks a different dialect is more, "You talk funny" versus "I can't understand you."
Alzhedo: Amn, Chult, Calimshan, the Lake of Steam, Lapaliiya, Lantan, the Nelanther Isles, the North (mostly Waterdeep, among dwarves, elves and gnomes), the Shaar, Tashalar, Tethyr, Tharsult, the Western Heartlands (among halflings and planetouched), Underdark (Old Shanatar), the Wealdath. A regional tongue of southwest Faerun, and the main language of Calimshan. Alzhedo is derived from Untheric and is in the same family as Midani. Sages believe that it shares some traits with the language of the elemental plane of air, as well. Written with Thorass.
Dialects: Amnian, Calimshani, D'tarig, Lantanese, Midani, Uloushinn
D'tarig: Anauroch. The tribal language of the D'tarig people of southeastern Anauroch, D'tarig is a throaty tongue that is part of the Uluo language family (along with languages such as Damaran and lost Netherese).
Lantanese: Lantan, Nelanther Isles, Tethyr. A regional tongue of southern Faerun, and the official language of Lantan. Written with Draconic.
Midani: Anauroch (Bedine). The language of the Bedine people of Anauroch is the same language of the distant lands of Zakhara. The bedine write with Thorass, as they lost their original written language.
Uloushinn: Anauroch. One of the native tongues of the Bedine of Anauroch, a blending of their original Midani with the tongues of Netheril they found in the deserts. Written with Thorass.
Chardic (aka Easting): Chardic is spoken by the people surrounding the Easting Reach (Impiltur, Thesk, The Great Dale, Aglarond, and Narfell) and was imported to Damara and Vaasa when the glaciers receded. It is a popular "second language" for the communities of the Vast.
Dialects: Aglarondan, Alambit, Allesian, Damaran, Impilturan, Vaasan, Naric.
Aglarondan: Aglarond, Altumbel, Chessenta, the Dragon Coast, Impiltur, Mulhorand, Rashmen, Thesk, the Vast. A regional tongue of eastern Faerun, and the official language of Aglarond. Aglarondan is a derivitive language of Thorass, and is in the same family as Turmic. Written with Espruar.
Alambit: Altumbel. A regional language spoken by the people of Altumbel and surrounding environs. Written in Thorass.
Allesian: Ashanath, Thesk. A regional language of Ashane and Thesk, with a number of dialects, including Ashane and Golden Allesian. Written in Thorass.
Damaran: Aglarond, Altumbel, the Anauroch, Cormyr, the Dalelands, Damara, the Dragon Coast, the Great Dale, the Great Glacier, the Hordelands, Impiltur, the Moonsea, Narfell, Rashemen, the Ride, Sembia, the Sandovar, Thay, Thesk, Vaasa, the Vast, the Vilhon Reach. A regional language of northeast Faerun and the official language of the kingdom of Damara. Damaran is an old language, descended from Ulou, the precursor language of Netherese. Written with Dethek.
Naric: Narfell. The regional language of the Nars people of Narfell. Written in Thorass.
Chondathan. The language of Chondath once stretched far beyond the current borders of that domain. It is the primary language of Chondath, Turmish, Chessenta and most of the lands nestled between the Shaar and the Sea of Fallen Stars from the Vilhon Reach to Mulhorand. An immensely ubiquitous language throughout most of central Faerun. Chondathan is derived from Thorass, and is related to Cormanthan and Northern. Written with Thorass.
Dialects: Chessic, Sespechian, Turmic, Untheric.
Chessic: Chessenta. Language of modern Chessenta. Written with Thorass.
Sespechian: Sespech, the Shining Plains. A regional language of Sespech and the Shining Plains. Written in Thorass.
Turmic: Turmish, Great Glacier. A relatively small-scope regional language spoken almost excusively in Turmish and the few folk on the Great Glacier. Written with Thorass.
Untheric: Chessenta, Unther. Untheric derives from an ancient language family called Rauric, along with Mulhorandi. Untheric was once spoken as a primary language in Chessenta, but has been relegated to a secondary language over the years, albeit one of polite society and bureaucracy. Written with Dethek.
Chultan. Spoken in the lands once part of the peninsula of Chult, Chultan is still the primary language from Chult to the walls of Halruaa. A regional dialect of southern Faerun, and the main language of Chult and Samarach. It is primarily spoken in the lands of Chult and the Mhair archipelago. Tribes in the Chultan jungles often speak Tabaxi, a language related to Chultan and named for the jaguar people of those jungles. Written with Draconic.
Dialects: Akalan, Akurian, Tashalan.
Akalan: Chult. A minor regional language spoken on the Chultan peninsula. Written in Thorass.
Akurian: Chult. A regional language spoken in the southern Chultan peninsula. Written in Thorass.
Tashalan: Black & Mhair Jungles, Samarach, Tashalar, Thindol. The official language of the city-states of Tashalar, and hardly spoken elsewhere, Tashalan has roots in Netherese, and shares many linguistic traits with Chultan. Written with Dethek.
Cormanthan: Derived from elven, this language was widely spoken when the Empire of Cormanthor was at its height. It is the language of the Dalelands, the Moonsea, Cormyr, Sembia, the Dragon Coast, and the Vast. Written with Espruar originally, but mostly with Thorass today.
Dialects: Andt, Erakic, Tharian.
Andt: Cormyr. The language of the marsh drovers in Cormyr's Farsea Swamp. Written with Thorass.
Erakic: The Ride. The language of the barbarians of the Ride. Written in Thorass.
Tharian: Moonsea (North and West). A regional language spoken by the Zhentish and around Phlan, Melvaunt, Glistern and the like. Written in Thorass.
Halruaan: Channath Vale, Dambrath, the Golden Water, Halruaa, Lapaliiya, Nimbral, the Shaar. The official language of Halruaa and a regional language of southern Faerun. Halruaan is derived from Netherese. Halruaan is primarily spoken in Halruua and Dambrath. Many of the hin of Lurien pick up Halruaan as a second language. Written with Draconic.
Dialects: Dambrathan
Illuskan: Moonshae Isles, the North (barbarians, Luskan, Mintarn), Ruathym. A regional language that traces back to the Illusk Empire. Derived from Netherese, this language is widespread in the Savage Frontiers and Sword Coast. Northman raiders have spread the language far and wide, and most of the northern Island Kingdoms (such as the Moonshaes and Nelanthar Isles) speak Illuskan as well.
Dialects: Bothii, Cosh, Northern, Reghedjic, Thorasta, Waelan, Waterdhavian
Bothii: the North (Northern). This is the language, related to Illuskan, spoken by the peoples of the Uthgardt and Hartsvale. Written with Thorass.
Cosh: Nelanther Isles. A vulgar patois made up of slang terms, euphemisms and outright degeneration of the Waelan language, used by smugglers and very rural folk in the Nelanther Isles. Written in Thorass.
Northern: the North. A regional language spoken mostly around the Ten Towns, Neverwinter, Waterdeep, Nesme and Llorkh. A fairly simple tongue largely going out of style. Written in Thorass.
Reghedjic: the North (Spine of the World). A language spoken by the Reghedmen of the Icewind Dale and other lands north of the Spine of the World. It is named for the Reghed Glacier, and is related to Illuskan. Written in Thorass.
Thorasta: Western Heartlands. A regional tongue spoken mostly between the Way Inn and Beregost, and Baldur's Gate to Hillsedge. Written in Thorass.
Waelan: Moonshae Isles. A unique, lilting tongue that shares some traits with Sylvan, as well as the language of druids (Drueidan, under Trade Languages, below). Written in Thorass.
Waterdhavian. For as long as even the oldest elves remember, there has been a settlement located in Deepwater Bay. Waterdhavian has its roots in Illuskan, the language of the north, but borrows heavily from Alzhedo due to ongoing trade and relationships with Amn, Tethyr, and Calimshan. Waterdhavian is becoming the primary dialect of the civilized areas of the North.
Mulhorandi: Chessenta, Mulhorand, Murghom, Semphar, Thay. A regional language of eastern Faerun, and the official language of both Muhorand and Thay. Mulhorandi derives from a language family called Rauric, along with Untheric. Written with Celestial, although the Thayan dialect of Mulhorandi utilizes Infernal in its writings.
Dialects: Alarric, Chessentan, Durpari, Thayan
Alarric: Durpar, Raurin, Var the Golden, Estagund. A regional language spoken by the people of Durpar and surrounding environs. Written in Thorass.
Durpari: Durpar, the Golden Water, Luiren, Mulhorand, Nimbral, the Shaar. A regional tongue of southeastern Faerun, and the official language of Durpar. Interestingly, it is also known by many Shou expatriates in Faerun. Written with Thorass.
Rashemi: Rashemen. An ancient language spoken almost exclusively in Rashemen and the siolated realm of Sossal. Written with Thorass.
Dialects: Rasallesian, Sossic
Rasallesian: Rashemen. One of several languages spoken in Rashemen. Written in Thorass.
Sossic: Sossal. The language of the Sossrim peoples, related to the Rashemi. Written in Thorass.
Shaaran: Amn, Calimshan, Chondalwood, Chult, Dambrath, Great Rift, Halruaa, Lake of Steam, Lapaliiya, Luiren, the Nelanther Isles, Sembia, Sespech, the Shaar, Talashar, Turmish, Unther, the Vilhon Reach, the Wealdath. The dominant regional language in southern Faerun, and the dominant language in the Shaar. Written with Dethek.
Dialects: Shaartan
Tuigan: Hordelands. The common language of the tribes of the Hordelands. Written with Thorass. Dialects: Chuchian, Raurindi
Chuchian: Plain of Horses, Hordelands. Language of the tribes of the Plain of Horses. Extremely precise - vagueness in terminology is considered insulting, with each place and thing having its own proper name.
Raurindi: Raurin. A rare tribal language spoken by the people of the Raurin. Written in Thorass. Uluik: Sea of Moving Ice: A tribal language in little use save by those who originated it, the Ulutiuns and Ice Hunters of the Sea of Moving Ice. Written in Thorass.
Dialects: Ulutiun
Aragrakh: Dragons. An ancient language, also known as "Old High Wyrmish", used as a formal ritual language by dragons. Woe to those who are not dragons that are overheard using it by wyrmkind. Written in Draconic.
Dialects: Auld Wyrmish, Yipyak
Auld Wyrmish: Dragons. Something of a common tongue among the different breeds of dragon, who each have their own tongues. Also sometimes called "Draconic," it is also spoken by many kobolds and wyverns. Written in Draconic.
Yipyak: Kobolds. A debased form of Auld Wyrmish that serves as a common tongue for kobolds. Written in Draconic.
Dethek: Faerûn. Dethek serves as a sort of "dwarven common" among the people of Moradin, allowing them to understand one another despite differences in regional racial languages, to say nothing of giving outsiders a language to speak to them respectfully while keeping them ignorant of necessary clan-only communications. Written in Dethek.
Dialects: Authlan, Duergan, Galenan, Kurit, Riftspeak, Shanatan
Authlan: Wild Dwarves. An ancient and simplified version of Riftspeak, with noticable Authalan and Chultan influences. Written in Dethek, although it is rare to find a literate wild dwarf.
Duergan: Duergar. Originally descended from Shanatan, this language has been deeply affected by the duergars' time in the Underdark. Written in Dethek.
Galenan: Shield Dwarves. The language of the eastern shield dwarves is spoken more frequently by its people, but it is also less pure, having been heavily influenced by Damaran. Written in Dethek.
Kurit: Arctic Dwarves. A dwarven dialect considered much polluted by other dwarves, given the degree it has been influenced by the human Uluik language. Written in Dethek.
Riftspeak: Gold Dwarves. A truly ancient dialect favored by the dwarves of the Great Rift, who care for and nurture the speaking of this language as carefully as they care for their gold. Written in Dethek.
Shanatan: Shield Dwarves. The language of the western shield dwarves. Sadly, with the near-shattering of dwarven society among the shield dwarves, not many even know the language any more, and only a rare few elders who truly value such things can actually converse in it. Urdunnir dwarves speak on older version of the language. Written in Dethek.
Daraktan: Orcs. A common language spoken by most orcs, although not many of them are literate. It evolved from the now-dead Hulgorkyn language. Written in Dethek.
Espruar: (aka Teu'Tel'Quessan) Faerûn. Originally the tongue of the moon elves, Espruar has become something of a lingua franca among elvenkind, providing a common language for its speakers. Written in Espruar.
Dialects: Alu'Tel'Quessan (aka Serusan, Sea Elven) Aril'Tel'Quessan (Avariel), Ar'Tel'Quessan (Sun Elven or High Elven), Or'Tel'Quessan (Wood Elven), Ssri'Tel'Quessir (Drow Elven, includes High Drow and Deep Drow)
Deep Drow: Drow Elves. Also called Low Drow or Drowic, this is the common language of the drow. Each community has its own dialect, but can reasonably understand one another. Written in Espruar.
High Drow: Drow Elves. A complex language with its own runic alphabet, it is primarily used by priestesses in ritual context and nobles when they wish to communicate above the heads of the rabble. Written in High Drow.
Serusan: Sea of Fallen Stars (Aquatic). Written in Espruar.
Ghukliak: Goblins, Hobgoblins, Bugbears. A rough and gutteral language well suited to discussing concepts of violence. Written in Dethek. Gnim: Gnomes. A staggeringly complex language, filled with all manner of words to discuss nuances of distinction. It is a language excellent for artistic, academic and engineering pursuits; indeed, many sages across the realms consider it to be a "scholar's language". Written in Dethek.
Jannti: Geniekind. The language of the janns serves as a sort of Common language for geniekind, who are notoriously suspicious about those seeking to learn their individual languages. Jannti can be written in Thorass or Draconic.
Jotun: Giants. A common tongue among giants, and possibly one of the oldest extant languages still in use. It shares roots with Thorass, and is written with Thorass.
There are also individual languages based off of Jotun, in use by various giantish subraces (all of which are written in Thorass):
Jotunalder: Giants. A ritualized language that is highly formalized and stilted. Those who speak Jotun can understand it well enough.
Jogishk: Ogres. A vulgar patois of Jotun and Common.
Jotunhaug: Hill and Mountain Giants. A rough, gutteral language which seems to be a corruption of Jotunise.
Jotunild: Fire Giants.
Jotunise: Frost Giants. The predecessor language to Jotunhaug.
Jostunskye: Cloud and Fog Giants.
Jostunstein: Stone Giants.
Jotunuvar: Storm Giants.
Luiric (aka Hinish): Considered the racial language of halflings, it is almost unheard of outside of Luiren or other hin strongholds. Written in Espruar.
Drueidan: Druids. The language of druids concerns itself with natural and spiritual concepts, providing a terminology for discussing the nuances of such things missing in other tongues. Speakers of Sylvan can begin to understand such discussions to limited extent. It may be written in Thorass, Espruar or Dethek.
Drow Sign Language: Drow Elves. A hand-code capable of impressive complexity, used by drow on patrol in the Underdark, or when silence is otherwise needful or useful.
Maiden's Tongue: Dambrath (Priestesses of Loviatar). The ceremonial and secret tongue of the Crintri priestesses of Loviatar in the nation of Dambrath. Written in Thorass.
Ruathlek: Illusionists, Followers of Lliira, Nimbral. A language derived from Netherese innovated by the ancient followers of Lliira and the cabals of illusionists in service to her. The language remains in use as a sort of trade language that many illusionist arcanabula are written in, as well as the language of Nimbral.
Thieves' Cant: Thieves and other Underworld types. A language made up of slang, reference to previous events in the criminal world and innuendo, thieves' cant changes from place to place, season to season. Part of knowing thieves' cant isn't just knowing what to say, as this changes constantly - it is the skill to figure out how to "hook into" the local cant and use it to communicate, a process that takes about an evening's worth of carousing. It has no written form.
Shadow Cant: Shadow Thieves of Amn. Originating with the Northern language, this cant was the secret code of the Shadow Thieves of Waterdeep. When they were cast out of the city and fled to Amn, it took on some other nuances of the local language as well. Northern Cant is a dead language, for all intents and purposes.
Zhentarim Argot: Zhentarim. The secret tongue of the Black Network. It is rarely spoken outside of Zhentarim strongholds, such as the Citadel of the Raven, Darkhold and Zhentil Keep, except by their nefarious agents meeting in secret. Written in Thorass.
Extraplanar
(1500EP) Abyssal: Demons. A twisted, complex tongue whose words often have meanings based on the speaker's emotions and intentions toward the listener, Abyssal's linguistic emphasis is on concepts of violence and revulsion, madness and contempt for others. Written in Infernal.
(1500EP) Celestial: Upper Planes. A transcendant tongue from which derives many languages' words for concepts of good, purity, justice, compassion, and beneficence. Written in Celestial.
(1500EP) Infernal: Devils. A vulgar, angry patois combining the worst of a thousand different tongues from across the multiverse, Infernal is a language of hate and domination, of invective and threat. Written in Infernal.
Primordial: Elementals. An ur-language made up of the limited elemental dialects found on the various Inner Planes. Native speakers can often speak only their individual dialect, but those who learn the tongue usually master all of the dialects as part of learning the complete language. These dialects include Auran (planes of Air), Aquan (planes of Water), Ignan (planes of Fire), and Terran (planes of Earth). Written in Dethek.
Shadovar. The tongue widely used in the Shadowfell. Spoken by Shadar-kai, Darklings (Dark Folk), and Shades.
Sylvan: Fey. A subtle language spoken by fey and many other sylvan creatures with close ties to such. Widely used in the Feywild. Written in Espruar.