atacamite

noun

at·​a·​cam·​ite

ˌatəˈkaˌmīt,

əˈtakəˌm-

plural -s

: a mineral Cu₂Cl(OH)₃ consisting of a basic copper chloride that is transparent or translucent and of various shades of green and occurs usually in prismatic orthorhombic crystals but also in crystalline aggregates or in massive form (hardness 3–3.5, specific gravity 3.75–3.77)

Word History

Etymology

French, from Atacama desert, its locality + French -ite

The Ultimate Dictionary Awaits

Expand your vocabulary and dive deeper into language with Merriam-Webster Unabridged.

1. Expanded definitions
2. Detailed etymologies
3. Advanced search tools
4. All ad-free

Discover what makes Merriam-Webster Unabridged the essential choice for true word lovers.

Start Your Free Trial Now