Green’s Dictionary of Slang

quamin n.

also quarmin
[Twi kwamé, a boy who is born on a Saturday]

(W.I.) an unsophisticated, ignorant person, a countrified person.

[[WI]C. Rampini Letters from Jamaica 88: The old African names [...] Quamin, full of tricks].
[WI]cited in Cassidy & LePage Dict. Jam. Eng. (1980).