indisposed (adj.) Look up indisposed at Dictionary.com
c.1400, "unprepared;" early 15c., "not in order," from in- (1) "not" + disposed; or else from Late Latin indispositus "without order, confused." Mid-15c. as "diseased;" modern sense of "not very well" is from 1590s. A verb indispose is attested from 1650s but is perhaps a back-formation of this.