a rigid circular band of metal or wood or other material used for holding or fastening or hanging or pulling; "there was still a rusty iron hoop for tying a horse"
the great circle representing the apparent annual path of the sun; the plane of the Earth's orbit around the sun; makes an angle of about 23 degrees with the equator; "all of the planets rotate the sun in approximately the same ecliptic"
an imaginary line around the Earth forming the great circle that is equidistant from the north and south poles; "the equator is the boundary between the northern and southern hemispheres"
a circle dividing a sphere or other surface into two usually equal and symmetrical parts
a crystalline rock that can be cut and polished for jewelry; "he had the gem set in a ring for his wife"; "she had jewels made of all the rarest stones"