[ nap ]
/ næp /


Geology. a large mass of rock thrust a considerable distance along a nearly horizontal fault plane or in an overturned anticlinal fold.
Geometry. one of the two equal sections of a cone.

Origin of nappe

1905–10, Americanism; < French: literally, tablecloth, cloth; Old French nappe, nape < Latin mappa; cf. napkin Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for nappe

/ (næp) /


a large sheet or mass of rock, commonly a recumbent fold, that has been thrust from its original position by earth movements
the sheet of water that flows over a dam or weir
geometry either of the two parts into which a cone (sense 2) is divided by the vertex

Word Origin for nappe

C20: from French: tablecloth
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