I. ˈfi-sh ə n, -zh ə n noun
Etymology: Latin fission-, fissio, from findere to split — more at bite
Date: circa 1617
1. : a splitting or breaking up into parts
2. : reproduction by spontaneous division of the body into two or more parts each of which grows into a complete organism
3. : the splitting of an atomic nucleus resulting in the release of large amounts of energy
• fis·sion·al -shə-nəl, -zhə- adjective
II. verb
Date: 1929
intransitive verb
: to undergo fission
transitive verb
: to cause to undergo fission