unflappable

adjective

un·​flap·​pa·​ble ˌən-ˈfla-pə-bəl 

: marked by assurance and self-control

has a reputation for being unflappable even in the worst situations

unflappability

ˌən-ˌfla-pə-ˈbi-lə-tē 

noun

unflappably

ˌən-ˈfla-pə-blē 

adverb

Synonyms of unflappable

• nonchalant
• calm
• imperturbable
• serene
• unshakable
• composed
• nerveless

Examples of unflappable in a Sentence

He has a reputation for being unflappable.

the unflappable teacher never even blinked when the wall map came crashing down

Recent Examples on the Web

Milo is also unflappable in the face of critics. —Stephanie Ganz, Parents, 5 Jan. 2026

Players say in that regard, McDaniel has been unflappable. —Chris Perkins, Sun Sentinel, 1 Jan. 2026

While Sammie is naive, impatient, and yearning for adulthood, Delta Slim is wise, heedless yeet unflappable, and the surprising steady voice when the juke joint descends into chaos. —Kathleen Newman-Bremang, Refinery29, 30 Dec. 2025

His biggest athletic foe comes in the unflappable form of Japanese table tennis star Koto Endo (Koto Kawaguchi), an icon in his homeland who Marty’s primary table tennis rival. —Randy Myers, Mercury News, 23 Dec. 2025

Word History

Etymology

un- entry 1 + flap entry 1 (state of excitement) + -able

First Known Use

1954, in the meaning defined above

Kids Definition

unflappable

adjective

un·​flap·​pa·​ble ˌən-ˈflap-ə-bəl 

: not easily upset or panicked : unusually calm