The origin of the term is that thing a girl does when she's plucking her eyebrows where she switches back and forthtrying to get things even, but accidentally takes too much off EVERY time until there is no eyebrow left.
Despite the origin, this term applies to haircuts, makeup, and even external things the girl does.
Jer: Your hair looks fine woman, stop eyebrowing!
Rosey: No wait, I'm almost done, my hair is uneven!
Jer: You are such an eyebrower!