sure thing

noun

1. something that is or is supposed to be a certain success, as a bet or a business venture.

   He thinks that real estate is a sure thing.

2. something assured; certainty.

   It's a sure thing that he'll refuse to cooperate.

interjection

1. surely; for sure; O.K.

sure thing

adverb

1. (sentence substitute) all right! yes indeed! used to express enthusiastic assent

noun

1. something guaranteed to be successful

Word History and Origins

Origin of sure thing¹

An Americanism dating back to 1830–40

Idioms and Phrases

a sure thing . A certainty, as in Making the bestseller list has been a sure thing for Stephen King . This usage originally alluded to a bet that one could not lose. [First half of 1800s]

Yes indeed, certainly, as in Are you coming tonight?—Sure thing! This use of the idiom as an interjection dates from the late 1800s.