Decaffeinate rhymes with:
hyphenate, alienate, assassinate, carbonate, chlorinate, concatenate, contaminate, cross-pollinate, decontaminate, denominate, determinate, detonate, discriminate, disseminate, dominate, eliminate, emanate, exterminate, fascinate, fulminate, germinate, halogenate, hydrogenate, hyphenate, impersonate, incriminate, inseminate, insubordinate, isocyanate, italianate, latinate, marinate, opinionate, originate, oxygenate, pollinate, predominate, procrastinate, rejuvenate, resonate, self-pollinate, subordinate, terminate, titanate, urinate
Decaffeinate sounds like:
decaffeinated, disappoint, disappointed, disband, disbanded