Try Our Apps


Avoid these words. Seriously.


[pahy-ruh-loo-sahyt, pahy-rol-yuh-sahyt] /ˌpaɪ rəˈlu saɪt, paɪˈrɒl yəˌsaɪt/
a common mineral, manganese dioxide, MnO 2 , the principal ore of manganese, used in various manufactures, as a decolorizer of brown or green tints in glass, and as a depolarizer in dry-cell batteries.
Origin of pyrolusite
1820-30; pyro- + Greek loûs(is) washing + -ite1 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
Cite This Source
Examples from the Web for pyrolusite
Historical Examples
British Dictionary definitions for pyrolusite


a blackish fibrous or soft powdery mineral consisting of manganese dioxide in tetragonal crystalline form. It occurs in association with other manganese ores and is an important source of manganese. Formula: MnO2
Word Origin
C19: from pyro- + Greek lousis a washing +-ite1, from its use in purifying glass
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Cite This Source
Word Origin and History for pyrolusite

"manganese dioxide," 1828, the name given in Roman times, when it was used, in a heated state, to de-colorize glass, from Greek elements pyro- "by heat, by fire" (see pyro-) + lysis "a loosening" (see lose).

Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source

Word of the Day

Nearby words for pyrolusite

Word Value for pyrolusite

Scrabble Words With Friends