ruò​wú​qí​shì

nonchalant

若无其事 (若無其事) ruò​wú​qí​shì
nonchalant idiom
as if nothing had happened; calm and composed; nonchalant

Although he was nervous inside, he smiled on the surface as if nothing were wrong.

Frequency

Movie subtitles
2.00 per million appears in 1% of films
Written text
2.45 per million

Sources

Definitions
CC-CEDICT