opal

As an adjective vorpal

is sharp or deadly.

As a noun opal is

a mineral consisting, like quartz, of silica, but inferior to quartz in hardness and specific gravity, of the chemical formula SiO₂·nH₂O.

As a proper noun Opal is

{{given name|female|from=English}} from the precious stone, invented in the nineteenth century.

As a noun opal is

opal.

As nouns the difference between opah and opal

is that opah is any of various large, colourful, deep-bodied pelagic fish of the family lamprididae while opal is opal.

As nouns the difference between oval and opal

is that oval is oval while opal is opal.

As nouns the difference between copal and opal

is that copal is a resinous exudation from various tropical trees used chiefly in making varnishes and printing ink while opal is opal.

As nouns the difference between pal and opal

is that pal is pole, post while opal is opal.

As nouns the difference between nopal and opal

is that nopal is a prickly pear cactus from the genus Opuntia, especially species: Opuntia cochinellifera while opal is a mineral consisting, like quartz, of silica, but inferior to quartz in hardness and specific gravity, of the chemical formula SiO₂·nH₂O.

As a proper noun Opal is

{{given name|female|from=English}} from the precious stone, invented in the nineteenth century.