on one's guard

1. 1.

   vigilant

   “on guard against con artists”

   “must remain on your guard in such a situation”

   Synonymson guardupon one's guardon your guard

   Similarwary

Questions about on one's guard

What does on one's guard mean?

on one's guard means "vigilant".

What is another word for on one's guard?

Close synonyms include on guard, upon one's guard, on your guard. Each sense on this page lists its own synonyms, because a word with several meanings rarely has one substitute that works for all of them.

Is on one's guard a common word?

on one's guard is banded "Rare" — specialist or archaic — most readers will not have met it. The band comes from how often the word appears in a large corpus of everyday English, not from an editor's impression.