absentminded
adj. B2 Upper Intermediate UK //ˌæbsəntmˈaɪndɪd// ab·sent·mind·ed
adj. forgetful or not paying attention to what is happening around you. You use this to describe someone who is not thinking clearly or is easily distracted.
adj. characterised by a lack of attention to one's surroundings or a tendency to forget things. Often used to describe a state of mental distraction or a lack of focus.
He is so absentminded that he often forgets his keys.
The professor was so absentminded during the lecture that he forgot to mention the final exam.
Her absentminded nature often led to small errors in her work, though her overall intelligence and creativity were undeniable.