absent-minded

adj.
Deep in thought and heedless of present circumstances or activities; preoccupied.

absent-mindedly ab'sent-mind'ed·ly adv.
absent-mindedness ab'sent-mind'ed·ness n.

adjective

So lost in thought as to be unaware of one's surroundings: absent, abstracted, bemused, distrait, faraway, inattentive, preoccupied. Idioms: a million miles away. See ability/inability, awareness/unawareness.

adj

Definition: unaware of events
Antonyms: alert, attentive, aware, observant

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