pondering

(verb) reflect deeply on a subject. Synonyms: chew over, think over, meditate, ponder, excogitate, contemplate, muse, reflect, mull, mull over, ruminate, speculate. Examples: "I mulled over the events of the afternoon." "Philosophers have speculated on the question of god for thousands of years." "The scientist must stop to observe and start to excogitate."

(adj) deeply or seriously thoughtful. Synonyms: brooding, broody, contemplative, meditative, musing, pensive, reflective, ruminative. Example: "Byron lives on not only in his poetry, but also in his creation of the 'byronic hero' - the persona of a brooding melancholy young man";."