plural -s
: a mineral (Mn,Mg,Ca,Pb)(AsO4)(OH)5 composed of a basic arsenate of manganese often with other elements (such as magnesium, calcium, lead) and occurring in black prismatic crystals and grains (hardness 4.5, specific gravity 3.5)

Word History


German synadelphit, from Greek synadelphos one that has a brother or sister (from syn- + adelphos brother) + German -it -ite

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Dictionary Entries Near synadelphite

Cite this Entry

“Synadelphite.” Dictionary, Merriam-Webster, Accessed 29 Mar. 2023.

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