dress-down
Friday
Because of the heat we've declared a dress-down day.由于天气炎热,我们宣布了一个便服上班日。
Every day is dress-down day when you work from home.
On a recent dress-down Friday at his office, he decided to wear his new trainers.
When the company introduced a dress down day, they arranged seminars to instruct staff on what to wear.