A religious order of Ireland and Scotland, said to have been founded in the sixth century by St. Columba. So called from the Gaelic cylle-dee (a house of cells) or ceilede (servants of God, ceile, a servant). Giraldus Cambrensis, going to the Latin for its etymology, according to a custom unhappily not yet extinct, derives it from colo-deus (to worship God).
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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