Punctuation rhymes with:
fluctuation, fluctuation, infatuation, self-perpetuation, situation, continuation, devaluation, discontinuation, evaluation, fluctuation, graduation, infatuation, insinuation, menstruation, overvaluation, reevaluation, revaluation, self-perpetuation, situation, undervaluation, valuation
Punctuation sounds like:
peniston, pennington, pfingsten, pinkston, punxatauney