Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.
GARMAN
As described in historical dictionaries
Patronymica Britannica (1860)
GARMAN. A-Sax. gar, a spear, and mnn. A spearman.
Surname type: Occupational name
Origin: English
Region of origin: British Isles
Country of origin: England
Religion of origin: Christian
Language of origin: English