adj. 25B6; adjective ALERT, sharp-eyed, sharp, eagle-eyed, hawk-eyed, having eyes like a hawk, keen-eyed, watchful, heedful, aware; on the lookout, on the qui vive, on guard, attentive, vigilant, having one's eyes open/peeled; informal beady-eyed, not missing a trick, on the ball.
inattentive.