subs. (colloquial).See quot. 1785. Hence any living source of alms or revenue.
c. 1696. B. E., A New Dictionary of the Canting Crew, s.v. MILCH-KINE.
1785. GROSE, A Classical Dictionary of the Vulgar Tongue, s.v. MILCH-COW. One who is easily tricked out of his property: a term used by gaolers, for prisoners who have money, and bleed freely.
1859. G. W. MATSELL, Vocabulum; or, The Rogues Lexicon, s.v.