Gaelic and Celtic Online Language Dictionaries

  Pan-Gaelic, Irish and Scots Gaelic-English Dictionaries Gaelic Dictionary Search - Search words in one or all of four Gaelic dictionaries: MacBain's An Etymological Dictionary of the Gaelic Language (Scottish Gaelic); MacFarlane's The School Gaelic Dictionary (Scottish Gaelic); Kelly's Fockleyr Gaelg - Baarle (Manx Gaelic); The Gramadach Lexicon(Irish Gaelic). Also included are alphabetical index to each of the dictionary accessible by clicking on their names.
SMO Index of Gaelic Dictionary Resources - Sabhal Mòr Ostaig's listing of Gaelic lexical resources; interface in Gaelic.
SMO Gaelic Dictionary Search - Sabhal Mòr Ostaig's Gaelic dictionary portal, with a large number of Gaelic-English dictionaries available for online searches.
SMO Stòr-dàta Briathrachais Gàidhlig - Online Gaelic dictionary compiled at Sabhal Mòr Ostaig, which includes lots of modern terminology; site is entirely in Gaelic.
SMO Dúil Bélrai - Online glossary of Medieval Irish (Old and Middle Irish) by Dennis King.
SMO Gaelic Thesaurus - Gaelic thesaurus from SMO.
Scottish Executive Faclair na Pàrlamaid / Dictionary of Terms (in PDF) - Online bilingual dictionary of Scots Gaelic-English at the official Scotland government site; in PDF format.
MacBain's Etymological Dictionary of the Gaelic Language - Downloadable copies of MacBain's etymological dictionary in Latin-1 text, compressed .gz format, and ASCII text.
MacFarlane's The School Gaelic Dictionary - Dictionary of Gaelic-English, browsable online or downloadable in plain text, HTML, or coded text.
MacEachen's Gaelic Dictionary (TXT format) - This dictionary was composed by Ewen MacEachen, a priest from Arisaig and noted Gaelic scholar, and was first published in 1842; it has been updated with minor corrections of orthography and meaning. For academic purposes the spelling should be checked against a more modern Gaelic dictionary. - Scottish resources, with a searchable online dictionary for Scottish-English and English-Scottish.
Irish Identity English-Irish Dictionary - Online HTML dictionary with English terms and their Irish equivalents.
Wentworth's Gaelic-English Dictionaries - Downloadable Gaelic-English dictionaries in MS Word document format.
Wentworth's English-Gaelic Dictionary - Downloadable English-Gaelic dictionary in MS Word document format.
English-Manx Dictionary - English words and phrases and their Manx equivalents, with text input. Irish Dictionary - A free Irish dictionaries for many languages; browsable online, with word searches, and downloadable data files. Manx Dictionary - A free Manx-English bilingual dictionary; browsable online, with word searches, and downloadable data files.
Téarmaí Ríomhaireachta/Computing Terminology - Glossary of computing terms in Gaelic.
Gaelic Computing Terminology - Glossary of computing terms in Gaelic.
Wentworth's Spellchecker for Scottish Gaelic - Downloadable spell-checking dataset for Scots Gaelic compatible with MS Office and other word-processing suites.



  Welsh, Breton, and Cornish Dictionaries

A Dictionary of the Welsh Language - Extremely comprehensive dictionary of Welsh with English definitions, a project started in 1921 and completed in 2002, with a downloadable PDF copy at the bottom of the page, available for personal use only.
University of Wales Welsh-English Online Dictionary - Online searchable bilingual Welsh-English dictionary. With over 250,000 entries, and searchable by parts of speech.
Welsh-German Online Dictionary - Online bilingual Welsh-German dictionary; interface in German and Welsh.
Welsh-Russian Online Dictionary - Online bilingual Welsh-Russian dictionary; interface in Russian. Welsh Dictionary - Free Welsh bilingual dictionaries for many languages; browsable online, with word searches, and downloadable data files.
Computing Terms in Welsh - Online dictionary of computing terms with their equivalents in Welsh.

Geriadur Breton-French Dictionary - Translation from French to Breton, with over 22,000 French words.
ABP Breton-French Online Dictionary - Online bilingual Breton-French dictionary; interface in French.
Breton-German Online Dictionary - Online bilingual Breton-German dictionary; interface in German and Breton.

A Handbook of the Cornish Language - By Henry Jenner: "This book is principally intended for those persons of Cornish nationality who wish to acquire some knowledge of their ancient tongue, and to read, write, and perhaps even to speak it. Its aim is to represent in an intelligible form the Cornish of the later period, and since it is addressed to the general Cornish public rather than to the skilled philologist, much has been left unsaid that might have been of interest to the latter, old-fashioned phonological and grammatical terms have been used, a uniform system of spelling has been adopted, little notice has been taken of casual variations, and the arguments upon which the choice of forms has been based have not often been given.".