-fiss-

a. [ L. fissilis, fr. fissus, p. p. of findere to split. See Fissure. ] 1. Capable of being split, cleft, or divided in the direction of the grain, like wood, or along natural planes of cleavage, like crystals. [ 1913 Webster ]

This crystal is a pellucid, fissile stone. Sir I. Newton. [ 1913 Webster ]

2. Fissionable. [ PJC ]

a. [ L. fissus (p. p. of findere to split) + E. lingual. ] (Zool.) Having the tongue forked. [ 1913 Webster ]

‖n. pl. [ NL., fr. L. fissus (p. p. o f findere to split) + lingua tongue. ] (Zool.) A group of Lacertilia having the tongue forked, including the common lizards. [ Written also Fissilingues. ] [ 1913 Webster ]

n. Quality of being fissile. [ 1913 Webster ]

n. [ L. fissio. See Fissure. ] 1. A cleaving, splitting, or breaking up into parts. [ 1913 Webster ]

2. (Biol.) A method of asexual reproduction among the lowest (unicellular) organisms by means of a process of self-division, consisting of gradual division or cleavage of the into two parts, each of which then becomes a separate and independent organisms; as when a cell in an animal or plant, or its germ, undergoes a spontaneous division, and the parts again subdivide. See Segmentation, and Cell division, under Division. [ 1913 Webster ]

3. (Zool.) A process by which certain coral polyps, echinoderms, annelids, etc., spontaneously subdivide, each individual thus forming two or more new ones. See Strobilation. [ 1913 Webster ]

4. (Physics) The act or process of disintegration of an atomic nucleus into two or more smaller pieces; called also nuclear fission. The process may be spontaneous or induced by capture of neutrons or other smaller nuclei, and usually proceeds with evolution of energy. [ PJC ]

a. Capable of undergoing nuclear fission; -- a property of certain isotopes of elements with heavy nuclei.
Syn. -- fissile. [ PJC ]

a. [ L. fissus (p. p. of findere to split) + palma palm. ] (Zool.) Semipalmate and loboped, as a grebe's foot. See Illust. under Aves. [ 1913 Webster ]

‖n. pl. [ NL. See Fissiparous. ] (Zool.) Animals which reproduce by fission. [ 1913 Webster ]