Mac is defined as a shortened term for a macintosh computer or mackintosh raincoat, or is a slang term for a male for whom you don't know his name.(noun)
See mac in Webster's New World College Dictionary
Origin: < Ir & Gael mac, son < OCelt *makkos, akin to *makwos, son > OWelsh map, Welsh mab, ap, son: see maiden
See mac in American Heritage Dictionary 4
Origin: From Mac-, a common prefix in Scottish and Irish surnames.
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