informal
US /ɪnˈfɔːr.məl/
UK /ɪnˈfɔːr.məl/
1.
having a relaxed, friendly, or unofficial style or manner
:
•
The meeting had an informal atmosphere.
•
She prefers to wear informal clothes on weekends.
2.
not according to strict rules or forms
:
•
The group has an informal agreement to meet every month.
•
The language used in text messages is often very informal.