The state of being informal or relaxed in appearance or behavior.

अनौपचारिकता

English Usage: His casualness at the meeting surprised everyone, as he often came off as very formal.

Hindi Usage: बैठक में उनकी अनौपचारिकता ने सभी को चौंका दिया, क्योंकि वह अक्सर बहुत औपचारिक लगते थे।