“Ooh now that’s got my dander up.” It’s an expression that means you’re cross.

It was a word first seen in writing in America, 1831. Dander stood for dandruff. So when your dander’s up it means you’re so angry it’s brought the dandruff off your scalp!

Audio recording of this being discussed on Radio 4 programme “Word of Mouth” here:

http://www.bbc.co.uk/programmes/p04rk4dp