Informal Bound to be successful or perform as expected: a sure-fire solution to the problem. (adjective)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "sure-fire" in a sentence
"Blasting Arabs is a sure-fire way to win back the hearts of France's rightwing voters."
"These folks insisted they had a sure-fire machine."
"Here, then, are my five sure-fire steps for becoming a successful entrepreneur, even during hard times: 1. Identify The Problem: What bothers you?"