Green’s Dictionary of Slang

dandruff n.

1. a head butt.

[UK](con. 1950s–60s) G. Tremlett Little Legs 92: I gave him the Glasgow Kiss or the Dandruff.

2. (US) light snow.

[US]L. Dills CB Slanguage.

SE in slang uses

In phrases

get one’s dandruff up (v.) [joc. corruption of the colloq. get one’s dander up + image of flecks of dandruff rising as one gesticulates with rage]

(US) to lose one’s temper.

Bernice ‘Feeding goats milk to bottle calves’ posting 2 Mar. at Homesteadingtoday.com 🌐 And the thing that makes me so mad and get my dandruff up is folks or dairies that process milk and sell it to stores tasting yukky.
swap dandruff (v.)

see under swap v.