un-in-ter-est-ed / ŭn-ĭn-trĭ-stĭd, ŭn-ĭn-tər-ĭ-stĭd, ŭn-ĭn-tə-rĕs-tĭd
1. having no interest; indifferent
There are no uninteresting things, only uninterested people.
Gilbert K. Chesterton, 1874 – 1936
A combination of the English negative prefix un- (not), akin to the Latin negative prefix in-, and the English adjective interested, which is ultimately derived from the Latin prepositional prefix inter- (between, among, within, involved with) and est the third person singular of the Latin verb sum, esse, fui, futurum (to be).
Thank you to Allen Ward for providing this etymology.