1. the ermine in its brown summer coat with black-tipped tail;
The Collaborative International Dictionary of English v.0.48:
Stoat \Stoat\, n. [OE. stot a stoat, horse, bullock; perhaps
originally only of male animals, and akin to D. stooten to
push, E. stutter; cf. Icel. st?tr a bull, Sw. stut a bullock.
Cf. Stot.] (Zool.)
The ermine in its summer pelage, when it is reddish brown,
but with a black tip to the tail. The name is sometimes
applied also to other brown weasels.
WordNet (r) 3.0 (2006):
n 1: the ermine in its brown summer coat with black-tipped tail