One day, some stoned happy chappy was thinking of things that rhymed with dandruff, and by some happy coincidence, along came a man inflicted with the 'druff, to which stoned happy chappy cried, 'Mandruff!'
And so it was. Do you see?
Hairdresser: ah jeez, your head is mandruff central, dude. You ever thought about modelling for christmas cards?
Dude: Oh christ no!