"Well, I am the most disinterested among you, after all," said the first speaker, "for I never wear black gloves, and I never eat lunch.
There are no more uses of "disinterested" in the book.
Show samples from other sources
All the Finches had straight incisive eyebrows and heavy-lidded eyes; when they looked slant-wise, up, or straight ahead, a disinterested observer would catch a glimpse of what May-comb called Family Resemblance.
Harper Lee -- Go Set a Watchman
He looks up at them, disinterested and maybe disgusted by the baby, because he wanders deeper into the recesses of the cluttered store to get away.