behaving in a calm and relaxed way; giving the impression that you are not feeling any anxiety synonym casual to appear/look/sound nonchalant “It'll be fine,” she replied, with a nonchalant shrug.
NAmE//ˌnɑnʃəˈlɑns//
noun [uncountable] synonym insouciance an air of nonchalance adverb He was leaning nonchalantly against the wall. “I already know,” she replied nonchalantly.See nonchalant in the Oxford Advanced Learner's Dictionary
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