Undulate (?), a. [L. undulatus undulated, wavy, a dim. from unda a wave; cf. AS. &unr_;&unr_;, Icel. unnr; perhaps akin to E. water. Cf. Abound, Inundate, Redound, Surround.] Same as Undulated.
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Undulate, v. i. To move in, or have, undulations or waves; to vibrate; to wave; as, undulating air.
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