de rigueur
1 of 1adjective/dərɪˈɡɝ/
1
required by etiquette or fashion norms, indicating it's currently popular or expected to wear
C2- Wearing a black tie to the event is de rigueur.
- For formal occasions, a tailored suit is de rigueur for gentlemen.
- At the gala, wearing heels was de rigueur for the ladies.
- In the workplace, business attire is de rigueur for professional appearances.
- Sunglasses are de rigueur for protecting your eyes and adding flair to your outfit.