a. 1. Having the nature of crust; pertaining to a hard covering; as, a crusty coat; a crusty surface or substance. [ 1913 Webster ]
2. [ Possibly a corruption of cursty. Cf. Curst, Curstness. ] Having a hard exterior, or a short, rough manner, though kind at heart; snappish; peevish; surly. [ 1913 Webster ]
Thou crusty batch of nature, what's the news? Shak. [ 1913 Webster ]