[mus.tang] n [MexSp mestengo, fr. Sp, stray, fr. mesteno strayed, fr. mesta annual roundup of cattle that disposed of strays, fr. ML (animalia) mixta mixed animals] (1808) 1: the small hardy naturalized horse of the western plains directly descended from horses brought in by the Spaniards; also: bronc
2. slang: a commissioned officer (as in the U.S. Navy) who has risen from the ranks