1. A translucent mineral consisting of hydrated silica of variable colour; some varieties are used as gemstones

Derived forms: opals

See also: opalize

Type of: mineral, opaque gem

Encyclopedia: Opal, Virginia Opal Opal, Wyoming Opal, WY

• decollation
• decolonisation
• decolonise
• decolonization
• decolonize
• decolor
• decolorise
• decolorize
• decolour
• decolourise
• decolourize
• decommission
• decompile
• decomposable
• decompose
• decomposer
• decomposition
• decomposition reaction
• decompositional
• decompound
• decompound leaf
• decompress
• decompressing
• decompression
• decompression sickness