Množina: armillas

ETYM Late Lat. armillarius, from Latin armilla arm ring, bracelet, from armus arm: cf. French armillaire. Related to Arm. /> Of or relating to bracelets.
Like or composed of rings.
Like, pertaining to or composed of rings. armillary sphere, celestial globe composed only of rings marking equator, tropics, etc.

Množina: armillary spheres

Model of the celestial sphere; used by early astronomers to determine the positions of stars.
Earliest known astronomical device, in use from 3rd century BC. It showed the Earth at the center of the universe, surrounded by a number of movable metal rings representing the Sun, Moon, and planets. The armillary sphere was originally used to observe the heavens and later for teaching navigators about the arrangements and movements of the heavenly bodies.
An old astronomical instrument composed of rings showing the positions of important circles of the celestial sphere.