Definition of surefire : certain to get successful or expected results a surefire recipe.

How do you use surefire in a sentence?

1. The film looks a surefire Oscar winner. 2. Running into the road like that is a surefire way to get hurt.

Where does the saying surefire come from?

As an affirmative meaning “yes, certainly” it dates from 1803, from Middle English meanings “firmly established; having no doubt,” and phrases like to be sure (1650s), sure enough (1540s), and for sure (1580s). The use as an adverb meaning “assuredly” goes back to early 14c.