ar·mil·lar·y sphere (ärmə-lěrē, är-mĭlə-rē)
n.
An old astronomical model with solid rings, all circles of a single sphere, used to display relationships among the principal celestial circles.

[TahlilGaran] American Dictionary ▲

armillary sphere
[Translation of French sphère armillaire, from Latin armilla, bracelet, from armus, shoulder. See ar- in Indo-European Roots.]

[TahlilGaran] American Dictionary ▲