Fission Definition

fĭshən, fĭzh-

fissions

noun

fissions

A splitting apart; division into parts.

Webster's New World

A nuclear reaction in which an atomic nucleus, especially a heavy nucleus, such as an isotope of uranium, splits into fragments, usually two fragments of comparable but unequal mass, and releases a few neutrons and about 100 million electron volts of energy. Nuclear fission may occur spontaneously or may be induced by the absorption of a neutron, which can initiate a nuclear chain reaction.

American Heritage

A form of asexual reproduction, found in various simple plants and animals, in which the parent organism divides into two or more approximately equal parts, each becoming an independent individual.

Webster's New World

Synonyms:

verb

To undergo or cause to undergo nuclear fission.

Webster's New World

To undergo fission.

American Heritage

Other Word Forms of Fission

Noun

Singular:

fission

Plural:

fissions

Origin of Fission

From Latin fissiōnem, accusative singular of fissiō (“the act of breaking up”), from findō (“split, divide”).

From Wiktionary
Latin fissiō fissiōn- a cleaving from fissus split fissi–

From American Heritage Dictionary of the English Language, 5th Edition