obvolute vs undulate

obvolute

adj
  • overlapping; contorted; convoluted 

  • Having two opposite leaves, each with one edge overlapping the nearest edge of the other. 

  • Having a circle of several leaves or petals which overlap in that manner. 

undulate

adj
  • sinuous, winding up and down. 

  • Changing the pitch and volume of one's voice. 

  • Wavy in appearance or form. 

verb
  • To cause to resemble a wave 

  • To appear wavelike. 

  • To cause to move in a wavelike motion. 

  • To move in wavelike motions. 

How often have the words obvolute and undulate occurred in a corpus of books? (source: Google Ngram Viewer )