Etymology
Advertisement
get off (v.)
"escape," c. 1600, from get (v.) + off (adv.). Sexual sense attested by 1973.
Related entries & more 
Advertisement
cop out 

by 1942, noun ("a cowardly escape, an evasion") and verb ("sneak off, escape, give up without trying"), American English slang, perhaps from cop a plea (c. 1925) "plead guilty to lesser charges," which is probably from northern British slang cop "to catch" (a scolding, etc.); as in cop a feel "grope someone" (1930s); see cop (v.). Sense of "evade an issue or problem" is from 1960s.

Related entries & more 
go south (v.)
"vanish, abscond," 1920s, American English, probably from mid-19c. notion of disappearing south to Mexico or Texas to escape pursuit or responsibility, reinforced by Native American belief (attested in colonial writing mid-18c.) that the soul journeys south after death.
Related entries & more 
at bay (prep.)
late 14c., originally often at the bay; see bay (n.3). Figurative use, of human beings in difficulties, is from c. 1400. The expression reflects the former more widespread use of at. The earlier form of the phrase was at abai, used of hunted animals, "unable to escape," c. 1300, from French.
Related entries & more 
Underground Railroad (n.)
"network of U.S. anti-slavery activists helping runaways elude capture," attested from 1847, but said to date from 1831 and to have been coined in jest by bewildered trackers after their slaves vanished without a trace. Originally mostly the term for escape networks in the (then) western states of the U.S.
Related entries & more 
Advertisement
smart money (n.)
"money bet by those in the know," 1926, from smart (adj.). The same phrase earlier meant "money paid to sailors, soldiers, workers, etc., who have been disabled while on the job" (1690s), from a noun derivative of smart (v.). Also "money paid to obtain the discharge of a recruit" (1760), hence "money paid to escape some unpleasant situation" (1818). Sometimes in legal use, "damages in excess of injury done."
Related entries & more