Vermin \Ver"min\, n. sing. & pl.; used chiefly as plural. [OE. vermine, F. vermine, from L. vermis a worm; cf. LL. vermen a worm, L. verminosus full of worms. See Vermicular, Worm.]

1. An animal, in general. [Obs.]

Wherein were all manner of fourfooted beasts of the earth, and vermin, and worms, and fowls. --Acts x. 12. (Geneva Bible).

This crocodile is a mischievous fourfooted beast, a dangerous vermin, used to both elements. --Holland.

2. A noxious or mischievous animal; especially, noxious little animals or insects, collectively, as squirrels, rats, mice, flies, lice, bugs, etc. ``Cruel hounds or some foul vermin.'' --Chaucer.

Great injuries these vermin, mice and rats, do in the field. --Mortimer.

They disdain such vermin when the mighty boar of the forest . . . is before them. --Burke.

3. Hence, in contempt, noxious human beings.

You are my prisoners, base vermin. --Hudibras.

Source: Webster's Revised Unabridged Dictionary (1913)