Inattentive, a.
Etymology: [Cf. F. inattentif.]
Not attentive; not fixing the mind on an object; heedless; careless; negligent; regardless; as, an inattentive spectator or hearer; an inattentive habit. I. Watts.
Syn. -- Careless; heedless; regardless; thoughtless; negligent; remiss; inadvertent. -- In`at*ten"tive*ly, adv. -- In`at*ten"tive*ness, n.
Shades of meaning
Fernald has no entry of its own for inattentive; he lists it under abstracted.
He lists it without comment; the entries above explain its neighbors.