Enter a clue or pattern or both:
The Clue
Barbershop-quartet member (10 letter answer)
The Answer
HARMONIZER
Tags
Notes
The answer HARMONIZER is so rare that it appears less than once every 2500 puzzles.
Definition
HARMONIZER as a noun:
1. (harmonizer, harmoniser) = a musician who sings or plays in harmony
2. (harmonizer, harmoniser) = a mediator who brings one thing into harmonious agreement with another