roll, undulate -- (occur in soft rounded shapes; "The hills rolled past")
roll, undulate, flap, wave -- (move in a wavy pattern or with a rising and falling motion; "The curtains undulated"; "the waves rolled towards the beach")
undulate -- (increase and decrease in volume or pitch, as if in waves; "The singer's voice undulated")
Overview of adj undulate
The adj undulate has 1 sense
undulate -- (having a wavy margin and rippled surface)