imperturbable

calm not capable of being excited 
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imperturbable

[adj] - not easily perturbed or excited or upset
Found on http://www.webdictionary.co.uk/definition.php?query=imperturbable

Imperturbable

Im`per·turb'a·ble adjective [ Latin imperturbabilis ; prefix im- not + perturbare to disturb: confer French imperturbable . See Perture .] Incapable of being disturbed or disconcerted; as, imperturbable gravity.
Found on http://www.encyclo.co.uk/webster/I/19

imperturbable

unflappable adjective not easily perturbed or excited or upset; marked by extreme calm and composure; `hitherto imperturbable, he now showed signs of alarm`; `an imperturbable self-possession`; `unflappable in a crisis`
Found on https://www.encyclo.co.uk/local/20974

imperturbable

imperturbable, imperturbably, imperturbableness 1. Not easily perturbed or excited or upset. 2. Marked by extreme calm and composure.
Found on http://www.wordinfo.info/words/index/info/view_unit/2197/

imperturbable

marked by extreme calm and composure
Found on https://www.vocabulary.com/lists/52473

imperturbable

marked by extreme calm and composure
Found on https://www.vocabulary.com/lists/388678

imperturbable

marked by extreme calm and composure
Found on https://www.vocabulary.com/lists/51955
No exact match found