Also found in: Dictionary, Thesaurus.
1. Involving or pertaining to the risk or possibility that someone may die. (Usually used before a noun.) As a police officer in this neighborhood, you end up facing life-or-death situations on a regular basis.
2. Extremely serious or of dire consequences; of imperative importance. We've got some life-or-death decisions to make at the next board meeting that will determine the fate of the company. Don't worry if you can't finish everythign by Friday. It's not life-or-death or anything.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.