Main entry: undulate
Definition: increase and decrease in volume or pitch, as if in waves
Usage: The singer's voice undulated
Main entry: undulate, flap, roll, wave
Definition: move in a wavy pattern or with a rising and falling motion
Usage: The curtains undulated; the waves rolled towards the beach
Main entry: ruffle, cockle, undulate, riffle, ripple
Definition: stir up (water) so as to form ripples
Definition: occur in soft rounded shapes
Usage: The hills rolled past
Main entry: undulate
Definition: having a wavy margin and rippled surface