mitosis (n.)

"process of nuclear division, splitting of the chromatin of a nucleus," 1887, coined in German from Greek mitos "warp thread," a word of uncertain etymology, + Modern Latin -osis "act, process." The term was introduced by German anatomist Walther Fleming (1843-1905) in 1882. So called because chromatin of the cell nucleus appears as long threads in the first stages. Related: Mitotic.