Wiktionary
knobhead
n. 1 (context British vulgar English) The glans penis 2 (context British pejorative vulgar English) A fool, idiot
Wikipedia
Knobhead
Knobhead is a massive ice-free mountain, high, standing south of the western end of the Kukri Hills and overlooking Ferrar Glacier and Taylor Glacier at their point of apposition, in Victoria Land, Antarctica. It was discovered by the British National Antarctic Expedition (1901–04) and so named because of its appearance.
Usage examples of "knobhead".
See when I was bouncing, wasn’t a week went by when I didn’t have some knobhead having a go at me.