In the phrase ‘sleep tight’ (USA, 1873), the adjective ‘tight’ is used as an adverb meaning ‘soundly’, i.e. ‘deeply and without disturbance’, as in the combination ‘tight asleep’ (USA, 1847).
meaning: ‘there is nothing to prevent someone or something from being successful’—from a late-19th-century metaphor specifically used of poker games with ‘a sky-high limit’ on stakes
meaning: ‘thoroughly dejected or disappointed’—appeared (1973) in Tyne and Wear (north-eastern England)—originated apparently in football parlance, in which it soon became a cliché
UK, 1857—characterised by savage violence or merciless competition—from Alfred Tennyson’s poem ‘In Memoriam’ (1850), in which ‘red in tooth and claw’ refers to Nature’s brutality
UK, 1835—mischievous or deceitful behaviour—alludes to the proverbial playfulness of monkeys—probably modelled on Bengali ‘bãdrāmi’; cf. modern Sanskrit ‘vānara-karman’, from ‘vānara’ (monkey) and ‘karman’ (action, work, employment)
USA—‘to look, or to feel, (like) a million dollars’, or ‘(like) a million bucks’: to look, or to feel, extremely good, or extremely attractive (early 20th century)—sometimes used in contrast to ‘like thirty, or 30, cents’: cheap, worthless (late 19th century)
robotically conformist or obedient—from The Stepford Wives (1972 novel by Ira Levin and 1975 film adaptation by Bryan Forbes), in which Stepford is the name of a superficially idyllic suburb where the men have replaced their wives with obedient robots
‘the milk in the coconut’: a puzzling fact or circumstance; alludes to the question of how the milk got into the coconut—of British-English origin (1832), not of American-English origin as stated by the Oxford English Dictionary
originally: a child wearing the house key tied around their neck and staying in the streets while their mother is at work—USA, 1935: a poor Afro-American woman’s child—USA & UK, WWII: a child whose mother was engaged in war industry
USA, 1901—Especially in ‘to have them rolling in the aisles’, the colloquial phrase ‘in the aisles’ is used in various expressions to suggest a wildly enthusiastic reaction, especially uncontrollable laughter, on the part of an audience.