knap
noun
[ nap ]
• the crest of a hill.
• "a pathway winding around the knap of a green hill"
Origin:
Old English cnæpp, cnæp .
knap
verb
• shape (a piece of stone, typically flint) by striking it, so as to make a tool or weapon or a flat-faced stone for building walls.
• "buildings made of knapped flint"
Origin:
late Middle English (in the sense ‘to knock, rap’): imitative; compare with Dutch and German knappen ‘crack, crackle’.