USA, 1811—based on the three principal components that make up a flintlock gun: ‘lock’ denotes the firing mechanism, ‘stock’ the handle or wooden shoulder-piece to which it is attached, and ‘barrel’ the tube down which the bullet is fired
to create trouble or a commotion—USA, 1840—a euphemism for synonymous phrases such as ‘to raise the Devil’ and ‘to raise hell’—from the name of the eldest son of Adam and Eve and murderer of his brother Abel
first recorded in a speech by Rev. George W. Bethune, transcribed in ‘Brief abstract of the fourth annual report of board of Managers of the New-York city Colonization Society’, published in ‘The American Christian Instructor’ of April 1836
Of American-English origin, the colloquial phrase ‘hot under (or ‘in’) the collar’ means ‘extremely exasperated or angry’. The earliest instance that I have found is from The Chicago Tribune (Chicago, Illinois) of 8th July 1869.
From the name of the American film actress Mae West, renowned for her generous bust, the informal noun ‘Mae West’, attested in 1940, denotes an inflatable life jacket, originally as issued to Royal Air Force aviators during World War II.
‘eggcorn’: alteration of a word or phrase through the mishearing or reinterpretation of one or more of its elements as a similar-sounding word—coined in 2003 on the website Language Log with reference to a misinterpretation of ‘acorn’ as ‘eggcorn’
A humorous alteration of ‘au revoir’ after the noun ‘reservoir’, the exclamation ‘au reservoir’ is first recorded in Little Pedlington and the Pedlingtonians (London, 1839), by the English author John Poole (1786-1872).
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.
‘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
‘to take the Fifth’: to decline to reveal one’s own secrets—from ‘to take the Fifth Amendment’: to appeal to Article V of the original amendments to the U.S. Constitution, which states that “No person […] shall be compelled in any criminal case to be a witness against himself.”