[1] : The Collaborative International Dictionary of English v.0.48

undulate \un"dulate\, 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.
   1913 webster

         breath vocalized, that is, vibrated and undulated.
                                                  --holder.
   1913 webster
see also:
undulated undulating 

[2] : The Collaborative International Dictionary of English v.0.48

undulating \un"dula`ting\, a.
   rising and falling like waves; resembling wave form or
   motion; undulatory; rolling; wavy; as, an undulating medium;
   undulating ground. -- un"dula`tingly. adv.
   1913 webster
see also:
un"dula`tingly 

Undulating >> U Words
Undulating, definition of term: Undulating
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