- on guard as an adjective:
- 1
on guard
adjective
1 on guard
Vigilant:
— On guard against con artists.
synonyms: on one's guard, on your guard, upon one's guard.
Moby thesaurus: Argus-eyed, all ears, all eyes, at bay, aux abois, aux aguets, canny, careful, cautious, circumspect, custodial, defensively, deliberate, discreet, eagle-eyed, gingerly, guarded, hawk-eyed, heedful, hesitant ... show more.
debug info: 0.0139