Definition of cesium
: a silver-white soft ductile element of the alkali metal group that is the most electropositive element known and that is used especially in photoelectric cells — see element table
Indulge Your Inner Word Nerd
Recent Examples of cesium from the Web
-
Stuhlinger wrote that cesium would make a more efficient propellant than rubidium.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cesium'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Origin and Etymology of cesium
New Latin, from Latin caesius bluish gray
First Known Use: 1861
Medical Dictionary
cesium
Medical Definition of cesium
: a silver-white soft ductile element of the alkali metal group that is the most electropositive element known and that is used especially in photoelectric cells—symbol Cs; see element table
Learn More about cesium
-
Spanish Central: Translation of cesium Nglish: Translation of cesium for Spanish speakers Britannica.com: Encyclopedia article about cesium
Seen and Heard
What made you want to look up cesium? Please tell us where you read or heard it (including the quote, if possible).
Writing? Check your grammar now!