mop head

Wiktionary

1. n. The end of a mop, to which the thrums or rags are fastened.
2. n. US A clamp for holding the thrums or rags of a mop.
3. n. A type of haircut similar to that worn by The Beatles in the early 1960s.

GNU Webster's 1913

1. n. [U.S.] A clamp for holding the thrums or rags of a mop.