What is "unalert"

Usage examples of "unalert".

He didn't use his breathing apparatus, not because he thought his bubbles would alert the unalert guard, but to see how hard it would be to traverse the tunnel without breathing.

The law was well known, the punishment for an armed approach death, for both the armed man and the unalert guards--unless pardoned by the Sh@ogun personally.

Though the lock made some noise the voices in the far room murmured on, unalerted to his presence.