- The definition of aplomb is a strong belief in yourself and the ability to remain calm under pressure.
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.
Origin: French literally , perpendicularity, equilibrium ; from à, to plush plomb, the metal lead: see plumb
Used by arrangement with John Wiley & Sons, Inc.
Origin: French, from Old French a plomb, perpendicularly : a, according to (from Latin ad-; see ad-) + plomb, lead weight (from Latin plumbum, lead).