What is the collective name for group of people in a meeting?

There isn't one specific collective noun for a group of people in a meeting. The most common way to refer to them would be simply as:

* The attendees

* The participants

* The group

* The people in the meeting

You could also use a more descriptive term based on the meeting's purpose, such as:

* The committee (if it's a committee meeting)

* The board (if it's a board meeting)

* The team (if it's a team meeting)

* The audience (if it's a presentation or lecture)

Let me know if you have any other questions!