Bust
mid 17th century (denoting the upper part or torso of a large sculpture): from French buste, from Italian busto, from Latin bustum ‘tomb, sepulchral monument’.
wiktionary
From French buste < Italian busto, from Latin būstum.
From a variant of burst. Compare German Low German basten and barsten(“to burst”).
etymonline
bust (n.1)
1690s, "sculpture of upper torso and head," from French buste (16c.), from Italian busto "upper body," from Latin bustum "funeral monument, tomb," originally "funeral pyre, place where corpses are burned," perhaps shortened from ambustum, neuter of ambustus "burned around," past participle of amburere "burn around, scorch," from ambi- "around" + urere "to burn." Or perhaps from Old Latin boro, the early form of classical Latin uro "to burn." The sense development in Italian probably is from the Etruscan custom of keeping the ashes of the dead in an urn shaped like the person when alive.
From 1727 as "trunk of the human body above the waist." Meaning "bosom, measurement around a woman's body at the level of her breasts" is by 1884.
bust (n.2)
variant of burst (n.), 1764, American English. For loss of -r-, compare ass (n.2). Originally "frolic, spree;" sense of "sudden failure" is from 1842. Meaning "police raid or arrest" is from 1938. Phrase ______ or bust as an emphatic expression attested by 1851 in British depictions of Western U.S. dialect. Probably from earlier expression bust (one's) boiler, by late 1840s, a reference to steamboat boilers exploding when driven too hard.
bust (v.)
"to burst," 1806, variant of burst (v.); for loss of -r-, compare ass (n.2). Meaning "go bankrupt" is from 1834. Meaning "break (into)" is from 1859. The slang meaning "demote" (especially in a military sense) is from 1918; that of "place under arrest" is from 1953 (earlier "to raid" from Prohibition). In card games, "to go over a score of 21," from 1939. Related: Busted; busting.