opal

¹

[ oh-puhl ]

noun

1. a mineral, an amorphous form of silica, SiO 2 with some water of hydration, found in many varieties and colors, including a form that is milky white.
2. an iridescent variety of this that is used as a gem.
3. a gem of this.

Opal

²

[ oh-puhl ]

noun

1. a female given name.

opal

/ ˈəʊpəl /

noun

1. an amorphous, usually iridescent, mineral that can be of almost any colour, found in igneous rocks and around hot springs. It is used as a gemstone. Composition: hydrated silica. Formula: SiO 2 . n H 2 O

opal

/ ō′pəl /

1. A usually transparent mineral consisting of hydrous silica. Opal can occur in almost any color, but it is often pinkish white with a milky or pearly appearance. It typically forms within cracks in igneous rocks, in limestones, and in mineral veins. It also occurs in the silica-rich shells of certain marine organisms. Chemical formula: SiO 2 ·nH 2 O.

Derived Forms

• ˈopal-ˌlike, adjective

Word History and Origins

Origin of opal¹

1350–1400; Middle English < Latin opalus < Greek opállios opal, gem; probably from a source akin to Sanskrit upala precious stone

Word History and Origins

Origin of opal¹

C16: from Latin opalus, from Greek opallios, from Sanskrit upala precious stone

Example Sentences

Opal Lee, often referred to as “the grandmother of Juneteenth,” will join the CNN anchor Victor Blackwell for a conversation the current state of affairs.

From New York Times

Found in the Lightning Ridge opal fields, NSW, the opalised jaws date back to the Cenomanian Age of the Cretaceous Period, between 102 million to 96.6 million years ago.

From Science Daily

The fossils were found by Elizabeth Smith and her daughter Clytie of the Australian Opal Centre in Lightning Ridge, who have spent decades working and searching over the opal fields.

From Science Daily

"Opal fossils are rare, but opalised monotreme fossils are infinitely more rare, as there's one monotreme fragment to a million other pieces. We don't know when, or exactly where, they'll turn up," Elizabeth Smith said.

From Science Daily

Fossilised pieces of the animal's jaw bone were found in opal fields in northern New South Wales, alongside evidence of several other ancient and now extinct monotreme species.

From BBC