Word Study
Wacke
CIDE DICTIONARY
Wacke, n. [G. wacke, MHG. wacke a large stone, OHG. waggo a pebble.].
A soft, earthy, dark-colored rock or clay derived from the alteration of basalt. [1913 Webster]
OXFORD DICTIONARY
Wacke, n. hist. a greyish-green or brownish rock resulting from the decomposition of basaltic rock.
Etymology
G f. MHG wacke large stone, OHG wacko pebble
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