timebomb

A timebomb is a bomb that is set to go off at a certain time in the future. timebombs can be dangerous because they can explode without warning.

The timebomb was set to go off in two hours.
The timebomb was set to go off in ten years, but it was discovered before then.

noun

A bomb that has a mechanism such that detonation can be preset to a particular time.

noun

A program designed to perform a destructive action at a certain date and/or time.

noun

A situation that threatens to have disastrous consequences at some future time.