unobservant

Definitions

Failing to notice things that are happening or present.

Lacking the habit of paying close attention to one's surroundings.

Examples

Being unobservant, he failed to notice the subtle changes in his friend's demeanor.

The unobservant detective missed the crucial clue that was lying in plain sight.

Synonyms

inattentive oblivious heedless unaware distracted negligent absent-minded

Antonyms

observant attentive alert vigilant perceptive watchful sharp-eyed