Synonyms and related words :
be abstracted, brood, brood over, cerebrate, chaw, chew over, chew the cud, cogitate, con over, conceive, consider, contemplate, debate, deliberate, deliberate over, deliberate upon, design, devise, digest, envisage, envision, frame, have in mind, have in view, introspect, meditate upon, mull, mull over, muse, muse on, muse over, perpend, plan, play around with, play with, ponder, ponder over, reflect, reflect over, reflect upon, revolve, ruminate, ruminate over, run over, scheme, speculate, study, think, think over, think up, toy with, turn over, weigh