Noun
1. a person you know well and regard with affection and trust;
"he was my best friend at the university"2. an associate who provides assistance;
"he's a good ally in fight""they were friends of the workers"3. a person with whom you are acquainted;
"I have trouble remembering the names of all my acquaintances""we are friends of the family"4. a person who backs a politician or a team etc.;
"all their supporters came out for the game""they are friends of the library"