absorbed, abstracted, buried in thought, cogitative, cognitive, concentrating, concentrative, conceptive, conceptual, conceptualized, contemplating, contemplative, deliberating, deliberative, engaged in thought, engrossed, engrossed in thought, excogitating, ideative, immersed in thought, lost in thought, meditating, meditative, mental, museful, musing, noetic, occupied, pensive, pondering, prehensive, preoccupied, rapt, reflecting, reflective, ruminant, ruminating, ruminative, serious, sober, speculative, thinking, thought, thoughtful, wistful, wrapped in thought