Stone tools resembling a knife were characteristics to the end period of the Paleolithic period, and they were made by blunting and exfoliating flakes like stone knives (blades) (i.e. Exfoliation was adjusted so that the sharp edge of flake would be partly remained like a knife blade and the rest of the edge would be blunted), and by forming the flakes into a shape similar to modern knives.
ナイフ形石器（ナイフがたせっき）とは、後期旧石器時代に特徴的な、石刃（刃器）などの剥片に刃潰し剥離（剥片自身がもつ鋭い側縁の一部をナイフの刃のように残し、ほかの側縁を鈍くつぶす調整剥離）を加え、現在のナイフに似た形に仕上げた石器である。