untumultuous

== English == === Etymology === From un- +‎ tumultuous. === Pronunciation === (UK) IPA(key): /ʌntəˈmʌltjuːəs/ === Adjective === untumultuous (comparative more untumultuous, superlative most untumultuous) Not tumultuous; calm, placid. Synonyms: imperturbable, serene; see also Thesaurus:calm