(of a lens) convex on one side and concave on the other and thickest in the center.
- ‘The Björk-Shiley convexo-concave prosthetic valve was introduced in 1979.’
- ‘The steady-state profile is convexo-concave, and the convexity has a width corresponding exactly to the area where the first term is dominant.’
- ‘A pad member 15 is securely attached to a concave side 13 of the convexo-concave member 11 and is made of absorbent cotton material.’
We take a look at several popular, though confusing, punctuation marks.