disinterested Look up disinterested at Dictionary.com
1610s, "unconcerned," the sense we now would ascribe to uninterested; with the sense of "impartial" going to disinteressed (c.1600). Modern meaning of disinterested is first attested 1650s. As things now stand, disinterested means "free from personal bias," while uninterested means "caring nothing for the matter in question."