ˈnap noun
( -s )
Etymology: French, tablecloth, cover, sheet — more at napkin
1.
[French nappe ( d'eau ), literally, sheet of water]
: a sheet of water falling from the crest of a weir
2. : a large mass thrust over other rocks by a recumbent anticlinal fold, by thrust faulting, or by a combination of both
3.
a. : sheet 6
b. : one of the two sheets that lie on opposite sides of the vertex and together make up a cone