Related Clues:
- Sing with your mouth closed
- Sing a wordless tune
- Fringe or tassel of short unwoven threads
- Boat engine sound
- Sing along without words
- Drone in America having completed miles
- Stink; buzz
- (Make a) monotonous sound
- Pluck, as a harp
- Sound the strings of a guitar, say
- Monotonous sound of personnel in corporation
- Keep one's mouth shut?
- (Make) a continuous rhythmic sound
- Make music on a kazoo, say
- Some repetition heard here? Proops's completed minute