The description of an 'oblivious person' can have a number ofinterpretations: .
are they 'oblivious' because their mind is always somewhereelse (inattentive, absent minded, …preoccupied, distracted)? .
are they 'oblivious' because they're only interested in whatconcerns themselves (self-centered, inconsiderate, indifferent,thoughtless)? .
are they 'oblivious' because the don't know or don't understand(uninformed, ignorant, incognizant, unwitting)? All of those synonyms are adjectives. The term 'oblivious person'is a noun phrase made up of the noun 'person' described bythe adjective 'oblivious'. There is no one word for an obliviousperson. As close to that is replacing the adjective 'oblivious'with another adjective (or combination of adjectives) like thoselisted, to form a new noun phrase that will better suit yourmeaning. (MORE)