undulate

(verb) stir up (water) so as to form ripples. Synonyms: ripple, ruffle, riffle, cockle.

(verb) occur in soft rounded shapes. Synonyms: roll. Examples: "The hills rolled past."

(verb) move in a wavy pattern or with a rising and falling motion. Synonyms: roll, flap, wave. Examples: "The curtains undulated." "The waves rolled towards the beach."

(verb) increase and decrease in volume or pitch, as if in waves. Examples: "The singer's voice undulated."

(adj) having a wavy margin and rippled surface.