The Oxford Thesaurus An A-Z Dictionary of Synonyms - thoughtfuladj.

1) considerate, kind, kindly, kind-hearted, compassionate, tender, sympathetic, attentive, solicitous, helpful, charitable: Wasn't it thoughtful of Simon to offer his help? 2 contemplative, pensive, reflective, musing, in a brown study, pondering, meditative, engrossed, introspective, rapt, wistful, brooding, wool-gathering, day-dreaming: Every time I mentioned Clarissa, he would become thoughtful. 3) prudent, wary, cautious, mindful, heedful, thinking, attentive, circumspect, careful, caring: The crew are ever thoughtful of the passengers' safety.