USA, 1964—‘canary in the coal mine’: an early indicator of potential danger or failure—from the former practice of taking live canaries into coal mines to test for the presence of toxic gases, the illness or death of the canaries serving as an indication that such gases were present
After Ambrose Burnside, Union general in the U.S. Civil War, ‘burnsides’ (1866) denotes thick side whiskers worn with a moustache and clean-shaven chin; on the pattern of ‘side whiskers’, it was altered to ‘sideburns’ (1875), itself altered to ‘sideboards’ (1882).
‘coward’—from Old-French ‘cuard’, probably referring to a frightened animal with its tail between its legs—from ‘cüe’ (Modern French ‘queue’), ‘tail’, and pejorative suffix ‘-ard’ (cf. ‘bastard’)—‘cowardy, cowardy custard’, alliterative nonsensical children’s phrase (19th century)
The noun ‘wolf whistle’ appeared in the USA in 1943—Wolf-whistling was popularised by the wolf, a cartoon character created by Tex Avery in Little Red Walking Hood (1937), which reappeared in Red Hot Riding Hood (1943).
Classical Latin ‘muscŭlus’, literally ‘a little mouse’, also denoted ‘a muscle of the body’, especially of the upper arm, from the resemblance of a flexing muscle to the movements made by a mouse; ‘muscŭlus’ was also used in the sense of ‘mussel’.
16th century—from the Latin adjective ‘praeposterus’, composed of the adverb ‘prae’ (‘in front’, ‘before’) and the adjective ‘posterus’ (‘coming after’, ‘following’, ‘next’), so that its literal sense is ‘next (placed) first’, ‘having first what should be coming after’.
from the 16th-century phrase ‘to set cock a hoop’, ‘to set (the) cock on (the) hoop’, apparently meaning ‘to put the cock (= spigot) on a barrel hoop and let the liquor flow prior to a drinking bout’—‘cock’ later equated with the fowl and ‘hoop’ with French ‘huppe’ (tufted crest)
The phrase ‘all behind, like a cow’s tail’ and its variants mean ‘left behind’ and ‘late in accomplishing a task’. They appeared in print in the mid-19th century in the USA, Australia and Britain.
UK, 1937, colloquial—‘to have done something more than oneself (or someone else) has had hot dinners’: used jocularly to emphasise the subject’s wide experience of a particular activity or phenomenon
‘yahoo’: rude, noisy or violent person—word invented by Jonathan Swift (1667-1745) as the name of a race of brutish creatures resembling men in Gulliver’s Travels (1726)—came to be applied to the orang-utan