vigilant

adjective

On the alert, as for danger or error; watchful. synonym: careful.

Watchful, as one who watches during the hours for sleep; ever awake and on the alert; attentive to discover and avoid danger, or to provide for safety; circumspect; cautious; wary.

Indicating vigilance.

Synonyms 1. Wakeful, etc. See watchful.

adjective

Attentive to discover and avoid danger, or to provide for safety; wakeful; watchful; circumspect; wary.

adjective

Watchful, especially for danger or disorder; alert; wary

adjective

carefully observant or attentive; on the lookout for possible danger