absent-minded
US /ˌæb.səntˈmaɪn.dɪd/
UK /ˌæb.səntˈmaɪn.dɪd/

1.
despistado, distraído
having or showing a habitually forgetful or inattentive disposition
:
•
He's so absent-minded that he often forgets where he parked his car.
Es tan despistado que a menudo olvida dónde aparcó su coche.
•
Her absent-minded professor walked into the wrong classroom.
Su profesor despistado entró en el aula equivocada.