- ring, halo, annulus, anulus, doughnut, anchor ring - a toroidal shape; "a ring of ships in the harbor"; "a halo of smoke"
--1 is a kind of toroid
--1 has particulars: fairy ring, fairy circle - annulus - (Fungi) remnant of the partial veil that in mature mushrooms surrounds the lower part of the stem
--2 is a kind of plant part, plant structure
--2 is a part of partial veil, velum