opal

As a noun opal

is opal.

As a proper noun flint is

a city in michigan.

As nouns the difference between opal and pebble

is that opal is opal while pebble is a small stone, especially one rounded by the action of water.

As a verb pebble is

to pave with pebbles.

As nouns the difference between ruby and opal

is that ruby is (cockney rhyming slang) a curry, short for ruby murray while opal is opal.

As a proper noun ruby

is .

As nouns the difference between opal and opal

is that opal is opal while opal is opal.

As a noun opal

is opal.

As an adjective undefined is

lacking a definition or value.

As nouns the difference between onyx and opal

is that onyx is (mineralogy) a banded variety of chalcedony, a cryptocrystalline form of quartz while opal is opal.

As an adjective onyx

is jet-black.

As a noun opal

is opal.

As an adjective borosilicate is

borosilicate (attributive).

As a noun opal

is opal.

As a proper noun eye is

(uk|colloquial) the comedic magazine.

As nouns the difference between vauxhall and opal

is that vauxhall is some type of attraction on a funfair while opal is opal.

As nouns the difference between opal and null

is that opal is a mineral consisting, like quartz, of silica, but inferior to quartz in hardness and specific gravity, of the chemical formula SiO₂·nH₂O while null is a non-existent or empty value or set of values.

As a proper noun Opal

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

As an adjective null is

having no validity, "null and void.

As a verb null is

to nullify; to annul.