uninterested

Disinterested and uninterested have a tangled history. Uninterested originally meant impartial, but this sense fell into disuse during the 18th century. About the same time the original sense of disinterested also disappeared, with uninterested developing a new sense—the present meaning—to take its place. The original sense of uninterested is still out of use, but the original sense of disinterested revived in the early 20th century. The revival has since been under frequent attack as an illiteracy and a blurring or loss of a useful distinction. Actual usage shows otherwise. The "free from selfish interest" sense of disinterested is still its most frequent sense, especially in edited prose; it shows no sign of vanishing. Further, disinterested has developed an additional sense—"no longer interested"—perhaps influenced by the "deprive of" sense of the prefix dis-, that contrasts with uninterested.

• • when I grow tired or disinterested in anything, I experience a disgust
  • —Jack London,  letter,  1914

Still, use of the "not interested" and "no longer interested" senses of disinterested will incur the disapproval of some who may not fully appreciate the history of this word or the subtleties of its present use.