Malapropisms

Malapropisms aren't just a case of picking the wrong word or garbling the right one – they improve on the original. Mrs Malaprop was a character in Sheridan's The Rivals who was always referring to allegories when she meant alligators, or epitaphs when she meant epithets.)

"She was shaking like a leaflet." (Strictly Come Dancing)

“And it’s all laid out by Calamity Brown.” John Major in the Queen’s garden.

defiantly not! for definitely not

“We’ll just bulstrode forward.” Nigel Leck on the Million Pound Property Experiment – I think he meant bulldoze.

When Mrs Friggins fainted in Penzance the “paramagics” came and looked after her.

The scene where the body of a dead Londoner who died of phenomena [pneumonia] ... submerging [emerging] from a submarine on a beach in Spain. ... (IMDB review of The Man Who Never Was)