[ad. L. fissiōn-em, n. of action f. findĕre to split.]
1. The action of splitting or dividing into pieces.
1865. Pop. Sc. Rev., Jan., 177. Fission, or the separation of cuttings, is used to perpetuate the same variety, whilst seeds, products of sexual reproduction, are used as the source of new varieties.
2. spec. in Biol. The division of a cell or organism into new cells or organisms, as a mode of reproduction.
1841–71. T. R. Jones, Anim. Kingd. (ed. 4), 49. In some elongated species the fission is effected in a longitudinal direction, the separation gradually proceeding from the posterior to the anterior extremity of the body.
1854. Owen, in R. Patterson, Zool., 38. A Medusa may actually be generated three successive times, and by as many distinct modes of generation—by fertile ova, by gemmation, and by spontaneous fission—before attaining its mature condition.
transf. 1882. T. K. Abbott, Our A B C, in Phonetic Jrnl., 9 Sept., 423/2. Vau had the singular fate of generating four other letters by a sort of spontaneous fission.
