noun
calmness, equanimity, serenity, self-possession, calm, collectedness, nonchalance, cool-headedness, control, self-control, sang-froid, aplomb, poise, balance, tranquillity, stability, harmony, concord, assurance, self-assurance, imperturbability, peace of mind, serene state of mind, inexcitability, dispassion, even temper, tranquil mind, coolness, level-headedness, placidity, fortitude, moderation, self-command, gravity, sobriety, a cool head, presence of mind, equilibrium, steadiness, self-restraint, repose, quiescence, imperturbation, ease, evenness, staidness, tolerance, dignity, quiet, quietude, command of one's faculties, equability, stoicism, forbearance, cool*, unflappability*, the even tenor of one's ways*; see also dignity 1, patience 1, peace 3, restraint 1.
Antonyms exuberance, passion*, wildness.
composure implies the disciplining of one's emotions in a trying situation or habitual self-possession in the face of excitement; equanimity implies an inherent evenness of temper or disposition that is not easily disturbed; serenity implies a lofty, clear peace of mind that is not easily clouded by ordinary stresses or excitements; nonchalance implies a casual indifference to or a cool detachment from situations that might be expected to disturb one emotionally; sang-froid implies great coolness and presence of mind in dangerous or trying circumstances
