PIE*bhregの「分ける」「壊す」から。 語源的にはbreak、fragment、fractionと同じ。 数学名詞に使われる。
Many important spatial patterns of Nature are either irregular or fragmented to such an extreme degree that ... classical geometry ... is hardly of any help in describing their form. ... I hope to show that it is possible in many cases to remedy this absence of geometric representation by using a family of shapes I propose to call fractals -- or fractal sets. [Mandelbrot, "Fractals," 1977]