combinations UK /kɒmbɪˈneɪʃənz/US /kɑmbɪˈneɪʃənz/ noun1 •A one-piece form of underwear, being a combination of a vest or chemise and underpants.“Put these on,” said Carrot firmly, anticipating resistance. “What is it?” said Catweazle in horror. “Coms. Combinations. A vest and long pants all in one,” explained Carrot. “They're jolly warm.” — 1970