From Longman Dictionary of Contemporary Englishundismayedun‧dis‧mayed /ˌʌndɪsˈmeɪd◂/ adjective formal not worried or frightened by something unpleasant or unexpected
Examples from the Corpus
undismayed• When Richard did not respond to his greeting except by frowning and then turning away, Hugh remained undismayed.• Joyce was undismayed by the subjugation of the Czechs. 