To settle, calm, or make less dangerous an extremely tense, hostile, or volatile situation. Likened to removing the fuse from or otherwise disabling a bomb. The shouting match between the two employees was getting increasingly aggressive, so the boss was brought in to defuse the situation. A special United Nations envoy was sent to defuse the conflict between the warring sects.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.