The Vase

I had a class for teachers, and the word of the day for me was the Vase. Should I say Vaes or Vahz? Vahz sounds fancier, and it's a fancy looking shape to make. It means I could allow my head to extend up and back. Never just tilted back as that looks dumb and can hurt vertabrae. Takes some getting used to, but maybe I'm ready to try since I have been working on strengthening the back of my neck for several years now.