not easily upset or confused, especially in a crisis; imperturbable.
Origin of unflappable
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Related Words for unflappabilityaplomb, composure, coolness, equanimity, imperturbability, nonchalance, poise, sang-froid, self-control, self-possession, stability, steadfastness
informal hard to upset; imperturbable; calm; composed
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