nonchalantly
/ˈnɒnʃ(ə)l(ə)ntli
/adverb
In a casually calm and relaxed manner: she nonchalantly walked out of the police station I shrugged nonchalantly...
- Jake shrugged nonchalantly, prudently ignoring Daniel's stupid comment.
- "It was all right," he replied nonchalantly.
- "So, where's Andrew?" Sam asked nonchalantly.