Sentence:  Where their sharp edges seemed restless as sea <WSD>waves</WSD> thrusting themselves upward in angry motion , Papa-san sat glacier like , his smooth solidity , his very immobility defying all the turmoil about him . 
Meaning of the word marked with <WSD> tags:  one of a series of ridges that moves across the surface of a liquid (especially across a large body of water)