Synonyms and related words :
brood over, chew over, con over, contemplate, deliberate over, deliberate upon, digest, excogitate, meditate upon, mind, mull over, muse on, muse over, perpend, ponder, ponder over, reevaluate, reexamine, reflect over, rethink, review, revolve, ruminate over, run over, study, turn over, weigh