Intonation rhymes with:
concatenation, destination, detonation, predestination, procrastination, abomination, alienation, antidiscrimination, assassination, combination, concatenation, contamination, coordination, coronation, culmination, decaffeination, decontamination, denomination, destination, determination, detonation, discrimination, disinclination, dissemination, divination, domination, elimination, emanation, examination, explanation, extermination, fascination, germination, hallucination, hydrogenation, hyphenation, illumination, imagination, impersonation, inclination, incoordination, incrimination, indoctrination, insemination, insubordination, machination, nomination, ordination, origination, pagination, pollination, predestination, procrastination, profanation, reexamination, rejuvenation, renomination, self-determination, subordination, termination, transillumination, vaccination
Intonation sounds like:
inattention, indentation, intention, intimation, intimidation