1. A meeting or sitting of a legislative or judicial body dealing with  business transactions: The U.N. Special Session on Disarmament is scheduled to take place next month.

The new session of the state legislature will deal with government properties going to private ownership in order to reduce some of the government debt.

2. The part of a year or of a day during which a school, college, or university has classes: Carol's children will be going to special classes during the summer session and then the elementary school will be back in regular sessions at the beginning of September.
3. An assembly of people for a common purpose or because of a special interest: The citizens of the village got together in a session to talk about and to decide on what needed to be done regarding the road conditions in their area.
4. U.S. law pertaining to the court of criminal jurisdiction: There will be a another legal session for the trial of the accused bank robber next week.
5. A period of time used or devoted to a specific activity: The sessions of recording the music by the local band will take place in a studio.

Bob's health insurance will cover just twelve one-hour sessions of therapy this year.