What is "serrating"

Usage examples of "serrating".

It seemed to have been carved out of foamy black lava, with the exposed pockets in the rock serrating every edge evenly.

Here it was a polished fine crystal pillar that spanned the entire height of the structure, hollowed out as the chair in the death chamber had been, only with peaked control projections serrating the edges where one of the sets of limbs rested.