Summary

Portrait of Alexander MacBain Alexander MacBain An Etymological Dictionary of the Gaelic Language (1911)

Gaelic belongs to the Celtic group of languages, and the Celtic is itself a branch of the Indo-European or Aryan family of speech; for it has been found that the languages of Europe (with the exception of Turkish, Hungarian, Basque, and Ugro-Finnish) , and those of Asia from the Caucasus to Ceylon,1 resemble each other in grammar and vocabulary to such an extent that they must all be considered as descended from one parent or original tongue. This parent tongue is variously called the Aryan, Indo-European, Indo-Germanic, and even the Indo-Celtic language.
Source: Wikisource

Portrait of Alexander MacBain Alexander MacBain An Etymological Dictionary of the Gaelic Language (1911)

The term Gaelic means Modern Gaelic.
Scottish Gaelic is written on the orthographic lines of Modern Irish, which in its turn represents the orthography of Old Irish. The greatest departure from ancient methods consists in the insistence now upon the rule of "Broad to broad and small to small." That is to say, a consonant must be flanked by vowels of the same quality, the "broad" being a, o, u, and the "small" e and i. Gaelic itself has fallen much away from the inflexional fulness of Old Irish.
Source: Wikisource

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