TITLE: What is the proper name of a "doughnut sector" or "curved trapezoid"?
QUESTION [8 upvotes]: What is the name of this shape? 

It is basically a sector with a doughnut hole cut out of it. Just wondering if it has a proper name.

REPLY [9 votes]: This is a sector of an annulus.  I would refer to it as an "annular sector".