Simple past tense and past participle of knap.(verb)
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Use "knapped" in a sentence
"These flints are hand knapped in England and are relatively uniform."
"According to Dr. Geist, Neanderthal's rough knapped stone spear heads would be perfact for slipping between the ribs of a large animal when thrust on a short spear."
"A new book from the crafter of the hyphenated superbole: "He sleep-otters under small black stones..." and later "illness's knapped letter is ribboned" in the "water-earth, the gonging.""