fissile

play
adjective fis·sile \ˈfi-səl, ˈfi-ˌsī(-ə)l\

Definition of fissile

  1. 1 :  capable of or prone to being split or divided in the direction of the grain or along natural planes of cleavage fissile wood fissile crystals

  2. 2 :  capable of undergoing fission

fissility

play \fi-ˈsi-lə-tē\ noun

fissile was our Word of the Day on 12/22/2014. Hear the podcast!

Recent Examples of fissile from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fissile'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Did You Know?

When scientists first used fissile back in the 1600s, the notion of splitting the nucleus of an atom would have seemed far-fetched indeed. In those days, people thought that atoms were the smallest particles of matter that existed and therefore could not be split. Fissile (which can be traced back to Latin findere, meaning "to split") was used in reference to things like rocks. When we hear about "fissile materials" today, the reference is usually to nuclear fission: the splitting of an atomic nucleus that releases a huge amount of energy. But there is still a place in our language for the original sense of fissile (and for the noun fissility, meaning "the quality of being fissile"). A geologist, for example, might refer to slate as being fissile.

Origin and Etymology of fissile

Latin fissilis, from findere



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