A joke.
The bard: So what do you call a singer who can't sing baritone or tenor or can't make his mind up?
Squonkhunter: Okay so you get...Soprano,Mezzo-soprano,Alto,Contralto,Tenor,Placido Domingo,Baritone,Bass-Baritone, Bass.
The bard: Makes sense doesnt it?
Simon from my comic HMS Crock Doctor. Had to trim it for the sake of spoilers.