self-possession

confidence, assurance, self-possession, aplomb mean a state of mind or a manner marked by easy coolness and freedom from uncertainty, diffidence, or embarrassment. confidence stresses faith in oneself and one's powers without any suggestion of conceit or arrogance.

• • the confidence that comes from long experience

assurance carries a stronger implication of certainty and may suggest arrogance or lack of objectivity in assessing one's own powers.

• • handled the cross-examination with complete assurance

self-possession implies an ease or coolness under stress that reflects perfect self-control and command of one's powers.

• • answered the insolent question with complete self-possession

aplomb implies a manifest self-possession in trying or challenging situations.

• • handled the reporters with great aplomb