As described in historical dictionaries

An Etymological Dictionary of Family and Christian Names (1857)

Tycwrdd, Welsh, a meeting-house. Tagair, Gaelic, to plead a cause, claim as a right, to reason, to debate.

Arthur, William (1857) An Etymological Dictionary of Family and Christian Names. New York: Sheldon, Blakeman. Public Domain.


Patronymica Britannica (1860)

TAGGART. The Gaelic Mac Taggart, sans \Iac.

Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.


Surname type: From given name or forename

Origin: Celtic

Region of origin: British Isles

Country of origin: Ireland

Religion of origin: Christian

Language of origin: Gaelic

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