English dictionary
opal
/'/oU/p/@/l/
Definitions, examples, synonyms and antonyms from WordNet 3.0.
noun
-
a translucent mineral consisting of hydrated silica of variable color; some varieties are used as gemstones
Source: WordNet 3.0
-
A mineral consisting, like quartz, of silica, but inferior to quartz in hardness and specific gravity.
Source: webster1913