mustangs

Noun

mustang (plural mustangs)

1. A small, hardy, naturalized (feral) horse of the North American west.
   • The mustang pony, the invariable companion of the inhabitant of the prairie, whether he is rich or poor, is a little creature, apparently narrow-chested, and small across the loins.1846, Thomas Bangs Thorpe, The Mysteries of the Backwoods, Carey and Hart, page 12
2. (US, slang) A merchant marine who joined the U.S. Navy as a commissioned officer during the American Civil War.
   • He is a product of the merchant marine and is one of the officers called "Mustangs" who entered the navy during the Civil War.1903, James Hoyt (editor), Seen & Heard by Megargee, L.N. Megargee, page 1754
3. (US, slang, generalized) A commissioned officer who started military service as an enlisted person.
   • […] and the chief engineer is a "mustang" — that is, an officer who has risen from the ranks of enlisted men.September-December 1918, Alfred Emanuel Smith, New Outlook, volume 120, Outlook Publishing Company, page 417

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