'Moonstone' definitions:
Definition of 'moonstone'
(from WordNet)
noun
A transparent or translucent gemstone with a pearly luster; some specimens are orthoclase feldspar and others are plagioclase feldspar
Definition of 'Moonstone'
From: GCIDE
- Moonstone \Moon"stone`\ (m[=oo]n"st[=o]n`), n. (Min.) A nearly pellucid variety of feldspar, showing pearly or opaline reflections from within. It is used as a gem. The best specimens come from Ceylon. [1913 Webster]