first thing adverb 2noun 1forms 1 adverb2 •Early in the morning.I'll meet you first thing at the station. •Straight away, very soon.Some of 'em said that when a boy had been away from home a couple of years he ought to want to see his folks the first thing. — 1916 noun1 •The basic idea of how to do something.I would help you, but I don't know the first thing about gardening. formsfirst things
