There are some meanings of pillock that my sainted and brilliant mother-in-law would feel uncomfortable about, so I'm sure she wouldn't have used the word. But one word she used all the time to describe an annoying person was "pill," as in, "Oh, she's such a pill!"
Rest her soul. She was one hell of a woman (and I've got a pretty good mother-in-law this time around, too - both were born in 1915).
-Joe-