ˈastrəˌlāb, ˈaas- sometimes -lab or -laa(ə)b noun
( -s )
Etymology: Middle English astrolabe, astrolabie, from Middle French & Medieval Latin; Middle French astrolabe, from Medieval Latin astrolabium, from Late Greek astrolabion, diminutive of Greek astrolabos, from astr- + -labos (from lambanein to take) — more at lemma
1. : a compact instrument for observing the positions of the celestial bodies, among the ancients often having been essentially the armillary sphere, in the 18th century a graduated circle for taking altitudes at sea, and now having been superseded by the sextant — see prismatic astrolabe
2. : a stereographic projection of the sphere on the plane of a great circle (as the equator or meridian) : planisphere
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