A Wizard's Staff Has A Knob On The End is a famous drinking song, first mentioned in Wyrd Sisters. Since the song is built around double entendres and risque, it is a popular song for Nanny Ogg tobelt it out to the night sky after a few drinks along with the also less-than-wholesome Hedgehog Song.
Being less worldly than Nanny Ogg, wizards find the song rather confusing and have been known to defensively ask just what is so funny about their staffs having knobs on the end, or about their insistence on polishing them. For foreigners who may likewise find themselves baffled, it's simple: staff, knob and "polishing the staff/knob" are all vulgar slang terms in British English referring to parts of the phallus, or to the act of male masturbation.
A version of the song, performed by Dave Greenslade, is available on the CD Terry Pratchett's From the Discworld.
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A knob on the end a knob on the end
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A knob on the end a knob on the end
A wizard when young has a staff that is small
It's puny and weak, ineffective withall
It grows with his power until it stands tall
As his fame and his glory expand
As his fame and his glory expand
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A knob on the end a knob on the end
The staff of a wizard can hold many spells
For finding lost objects or dowsing new wells
For banishing demons to bottomless hells
And bringing them back on demand
And bringing them back on demand
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A knob on the end a knob on the end
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A knob on the end a knob on the end
When a wizard is old, and is starting to fade
He looks on his staff that with cunning he made
The crown of his life and the tool of his trade
Together they make their last stand
And together they make their last stand
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A knob on the end a knob on the end
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A wizard's staff has a knob on the end
A knob on the end a knob on the end