lower (one's) guard

To become less guarded or vigilant; to stop being cautious about potential trouble or danger. We'll wait long enough for them to lower their guard before we launch our invasion. There will always be people in this business looking to exploit you, so you can never lower your guard.

Common Names:

Name	Pronounced	Usage
Eustachys	-	Ancient Greek
Anacletus	-	Ancient Greek (Latinized)
Norwood	['nɔ:.wud]
Lavrenty	-	Russian
Stern	[stə:n]
Boyce	[bɔis]