Un·du·late v. t. [imp. & p. p. Undulated p. pr. & vb. n. Undulating.] To cause to move backward and forward, or up and down, in undulations or waves; to cause to vibrate.
     Breath vocalized, that is, vibrated and undulated.   --Holder.
  Un·du·la·ting, a. Rising and falling like waves; resembling wave form or motion; undulatory; rolling; wavy; as, an undulating medium; undulating ground. -- Un*du*la*ting*ly. adv.
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