wet horse
n.— «Wet horse. Stolen horse. (From the fact that raiders ran the herds of stolen horses across the Rio Grande River.)» —“Cow Punchers’ Slang and Jargon” in Utah, Texas, Ore., S.D., Colo., Ariz., Mont. Lexicon of Trade Jargon , 1938-39. (source: Double-Tongued Dictionary)
Further reading
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