To get one’s dander up means to become angry, to become agitated enough to fight, whether literally or figuratively. Get one’s dander up is an American idiom, there are two possible origins. One theory is that get one’s dander up was a comedic way to express raise one’s hackles, referring to the dander or dandruff that would be stirred by the raising of hackles. The other origin theory concerns the fact that dander once referred to the froth resulting from the brewing of yeast. Getting one’s dander up would therefore draw a picture of billowing froth, a good metaphor for becoming angry.
Get one’s dandruff up is an eggcorn, a misheard rendering of a popular idiom, word or phrase.
Just to get his dander up, she’d ask him why he would even consider doing Romeo and Juliet. (The Edmonton Journal)
Because the great danger is that Andrew will get his dander up and let loose with some whacky claim that threatens to make things even worse. (The Huffington Post)
Correspondent Jessica Williams dug into it last year, but Stewart himself admitted in 2013 that “I can be incredibly certain about so many issues and get my dander up.” (Vanity Fair)
“But I do know that moving former the Eldorado High sensation from quarterback to tight end has my dander up. … I realize that the way second-year Michigan football head coach Jim Harbaugh runs his program makes Nick Saban look like he’s running a day care, but can’t we still get a tidbit of information here?” (The Free Detroit Press)
Anyway, just two days after organisers were insisting that the game would certainly take place in Dharamsala, it has been moved to Eden Gardens, Kolkata, although the Pakistan Cricket Board has its dander up and has yet to dispatch its team, and some like former great Imran Khan think the game should not proceed at all. (The Australian)