WordNet sense 1 (an undulating curve):

undulation

WordNet sense 2 (one of a series of ridges that moves across the surface of a liquid (especially across a large body of water)):

moving ridge

WordNet sense 3 (the act of signaling by a movement of the hand):

wafture, waving

WordNet sense 4 (move in a wavy pattern or with a rising and falling motion):

flap, roll, undulate

WordNet sense 5 (move or swing back and forth):

brandish, flourish

WordNet sense 6 (twist or roll into coils or ringlets):

curl

WordNet sense 7 (signal with the hands or nod):

beckon