1 : (often plural) a command given by a superior (e.g., a military or law enforcement officer) that must be obeyed
2 : an association of practitioners of a given profession
3 : an authoritative direction or instruction to do something
4 : something that is commanded
5 : an orderly arrangement
6 : an association of sports teams that organizes matches for its members
7 : an unofficial association of people or groups
8 : people engaged in a particular occupation