Irish English, 1829—‘in a fortunate or prosperous state’—a loan translation from Irish ‘ar mhuin na muice’, meaning, literally, ‘on the pig’s back’, and, figuratively, ‘in a fortunate or prosperous state’
USA, 1986—something intended to divert attention from something more important—refers to the fact that when two male gorillas confront each other, they throw dust in the air to distract one another—popularised, if not coined, by Henry Ross Perot
UK, 1921—‘frogspawn’: a jocular appellation for ‘tapioca pudding’ (also for ‘sago pudding’)—originated in schoolchildren’s slang—refers to the fact that both tapioca pudding and sago pudding very much resemble frogspawn, i.e., a soft substance like jelly which contains the eggs of a frog
Australia, 1937—very scarce—‘rocking horse’: a toy horse mounted on rockers or springs for a child to sit on and rock to and fro—this phrase has come to be also used in British English and American English
Australia, 1982—a coded signal from a man to other men, indicating that a woman is approaching, so that they all moderate their language—originally used in shearing sheds, but now used in other places, especially in pubs
Australia, 1930—a humorous extended form of ‘flat out’, meaning ‘with the maximum speed or effort’ (apparently with wordplay on ‘flat out’, meaning ‘lying stretched out’)—has occasionally been used in the opposite sense
Australia, 1972—a person, usually a man, who, in spite of a superficial smartness, is untrustworthy—‘rat’ refers to a deceitful or disloyal man—the image is that, despite the gold tooth, a rat’s basic nature cannot change
Australia, 1928—an outstandingly good person or thing—variant of the synonymous jocular expressions, of U.S. origin, based on various parts of animals’ real or fanciful anatomy and other attributes, such as ‘the bee’s knees’ and ‘the cat’s whiskers’