A friend; a pal.

“I ran into an old chum from school the other day.”

A roommate, especially in a college or university.

To share rooms with someone; to live together.

To lodge (somebody) with another person or people.

To make friends; to socialize.

To cast chum into the water to attract fish.

A coarse mould for holding the clay while being worked on a whirler, lathe or manually.