Brig
来自Big Physics
early 18th century: abbreviation of brigantine (the original sense).
wiktionary
Abbreviated from brigantine, from Italian brigantino; in sense “jail”, from the use of such ships as prisons.
From Scots brig, from Old Norse bryggja, from Proto-Germanic *brugjǭ. Doublet of bridge.
Clipping of brigadier
etymonline
brig (n.)
"two-masted square-rigged vessel," 1720, colloquial shortening of brigantine (q.v.). Meaning "a ship's jail" is by 1841, American English, perhaps from the use of such vessels as prison ships upon retirement from active duty.