unflappable vs imperturbable

unflappable and imperturbable both are adjectives.

Word	Noun	Adjective	Verb	Adverb
unflappable	No	Yes	No	No
imperturbable	No	Yes	No	No

As adjectives, unflappable and imperturbable are synonyms defined as:

unflappable and imperturbable: not easily perturbed or excited or upset; marked by extreme calm and composure

unflappable (adjective)	imperturbable (adjective)
not easily perturbed or excited or upset; marked by extreme calm and composure	not easily perturbed or excited or upset; marked by extreme calm and composure