Shaped like the capital letter "B" or its mirror image

Shaped like the capital letter "O", circular.

Shaped like the capital letter "R" or its mirror image

Shaped like the capital letter "I" with serifs. / Shaped like the capital letter "I" without serifs.

Having the hollow form of a cup (but without the handle)

Having the characteristic shape of a mushroom (as a pillar with a broad, circular top)

Having the shape of a leaf

Having the shape of a ring; circular; annular.

oval (especially in relation to eyes)

(botany) Shaped like a spinning top.