Association

1.  An organization of people that is not incorporated.  In general, an association is not a separate entity from the persons who compose it.  However, some laws may require associations to pay taxes, particularly if they have certain features that make it look like a corporation (e.g., central management, continuous existence, and some kind of limited liability that shields individual members from suit).

2.  General description for the act of meeting people and sharing ideas (e.g., "freedom of association" under the First Amendment of the U.S. Constitution).