cas ‧ u ‧ al ‧ i ‧ za ‧ tion BrE AmE ( also casualisation British English ) /ˌkæʒuəlaɪˈzeɪʃ ə n $ -lə-/ noun [uncountable]
1 . a tendency to make things less formal in places where people work, for example by allowing office workers to wear informal clothes
2 . a tendency for companies to use temporary workers instead of permanent ones