Decaffeinated rhymes with:
hyphenated, decontaminated, denominated, emanated, exterminated, germinated, halogenated, hydrogenated, hyphenated, impersonated, indoctrinated, marinated, opinionated, predominated, rejuvenated, renominated, resonated, subordinated
Decaffeinated sounds like:
decaffeinate, disappoint, disappointed, disband, disbanded