a formal meeting or series of meetings of an organization such as a parliament or a court of law

The parliamentary session is due to end on 27 May. 议会会议将于5月27日结束。

The UN Security Council met in emergency session to discuss the crisis. 联合国安理会举行了紧急会议讨论这一危机。

a period of time or meeting arranged for a particular activity

The 21-year-old runner twisted his ankle in a training session last Friday. 这位21岁的赛跑运动员上周五在训练时扭伤了脚踝。

As the European heads of state gathered, the press were allowed in for a photo session. 欧洲国家首脑聚集起来时，新闻记者获准进入拍照。

UK informal The men had a heavy session last night (= they drank a lot of alcohol). 昨晚男人们喝了很多酒。

at a college, any of the periods of time that a teaching year or day is divided into, or the teaching year itself

He taught a class during the summer session. 在夏季开学期间他教了一堂课。

Access is restricted when school is in session. 学校上课时间是不能随便进入的。