Coy m
U.S.: of uncertain origin. It is hardly likely to be from the modern English vocabulary word, which has both feminine and pejorative connotations. It probably represents a transferred use of the surname Coy, or it may be of Irish origin (from McCoy, a variant of McKay, meaning ‘son of Aodh’; Aodh was an old Gaelic name meaning ‘fire’).
First names dictionary. 2012.