* Meeting: This is the most common noun form, referring to a gathering of people for a specific purpose.
* Meet: In some cases, "meet" can act as a noun, particularly when referring to a particular point or location where people come together, such as "the meet of the river and the sea."
* Encounter: This noun refers to a chance or unplanned meeting.
The best noun form to use will depend on the specific meaning you want to convey.