Synonyms and related words :
aplomb, assurance, balance, composure, confidence, constraint, control, discipline, equability, equanimity, equilibrium, independence, level head, levelheadedness, poise, possession, presence of mind, restraint, self-assurance, self-confidence, self-conquest, self-containment, self-control, self-denial, self-discipline, self-government, self-mastery, self-possession, self-restraint, uncommunicativeness, well-regulated mind, willpower