The definition of aplomb is a strong belief in yourself and the ability to remain calm under pressure.(noun)
To know with certainty that you are the best person for the job and then to perform it well is an example of performing a job with aplomb.
See aplomb in Webster's New World College Dictionary
Origin: Fr, lit., perpendicularity, equilibrium < à, to + plomb, the metal lead: see plumb
See aplomb in American Heritage Dictionary 4
Origin: , from Old French a plomb, perpendicularly
Origin: : a, according to (from Latin ad-; see ad-)
Origin: + plomb, lead weight (from Latin plumbum, lead).
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