noun Etymology: French, literally, perpendicularity, from Middle French, from a plomb, literally, according to the plummet Date: 1823 complete and confident composure or self-assurance ; poise , see: confidence
APLOMB
Meaning of APLOMB in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012