noun, verb ·Moderate ·High school level

Definitions

Noun

1. 1
   The process whereby one item splits to become two. countable, uncountable
2. 2
   a nuclear reaction in which a massive nucleus splits into smaller nuclei with the simultaneous release of energy wordnet
3. 3
   nuclear fission: The process of splitting the nucleus of an atom into smaller particles. countable, uncountable
4. 4
   reproduction of some unicellular organisms by division of the cell into two more or less equal parts wordnet
5. 5
   The process by which a bacterium splits to form two daughter cells. countable, uncountable

Verb

1. 1
   To cause to undergo fission. transitive
2. 2
   To undergo fission. intransitive

Synonyms

All synonyms

ablateabscissionaccelerateactivatealpha decayamputation

Antonyms

All antonyms

fusion

Example

More examples

"Nuclear power plants rely upon the fission of uranium to generate heat."

Etymology

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

Related phrases

atomic fissionbinary fissionfission bombfission fragmentfission productfission rocketfission-fusion societyinduced fissionnuclear fissionspontaneous fissionfission bombnuclear fission

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.