1.
a company dress code: the rules or policy for what employees can and cannot wear to work
- We have a very strict company dress code. Every employee must wear formal business attire.
- Does your company have a company dress code or can you where whatever you want?
2.
business attire: clothes appropriate for business
- All employees must wear appropriate business attire.
- The boss told him to wear business attire, but he showed up wearing jeans and a T-shirt. The boss was very angry.
3.
to dress casually: to dress in a more relaxed and less formal way
- We can dress casually at my company.
- Salesman must dress formally at my company, but engineers can dress casually.