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adj. Moving up and down like waves; wavy

adj. Forming a series of regular curves

v. Present participle of undulate.

adj. Rising and falling like waves; resembling wave form or motion; undulatory; rolling; wavy.

Waving; vibrating; moving in waves.

Having a form or outline resembling that of a series of waves; wavy.

In zoology, undulate.

"Two flags were stiffly undulating from the halyards like squares of flexible sheet-iron."

billowy    sinuous   

undulatory    rolling    wavy    undulous    fluctuant    rippling    wave   

undulate