Webster's Revised Unabridged Dictionary · 1913

Mac

Mac , proper noun

Shortened form of Macintosh, a brand name for a personal computer; as, the latest Mac has great new features.

Mac

[Gael., son.]

A prefix, in names of Scotch origin, signifying son.

mac , noun

Shortened form of mackintosh, a waterproof raincoat made of rubberized fabric.