Bio break refers to a general break for one's body: stretching one's legs, going to the bathroom, getting a drink of water, etc. The term is generally used during meetings, presentations, and other workplace occasions1.

Bio break（字面意思为生理休息）指让身体稍事放松的小憩时间，大伙可以伸伸腿，去下厕所，打杯水等等，这里译为会间小憩。这个词多用在会议、演示讲坛等职场活动中。

For example:

Let's take a 10 minute bio break and be back in our seats at 3:30.

大家会间休息十分钟，请在3点30分回到座位。