caesium

noun (caesium — uncountable)

«caesium» in the English dictionary: everyday — its meanings, how the lessons use it, and examples, each with its tree on Mova.

Everyday

Caesium is a soft, silvery-gold metal, a chemical element (symbol Cs) that reacts violently with water. tree →
Caesium is used in atomic clocks, the most accurate clocks there are. tree →

In the lessons

In science lessons on elements and the periodic table (group 1 alkali metals with sodium and potassium); in maths and science, time: the second is defined using caesium atoms; in news about nuclear accidents, radioactive caesium.

Examples

Caesium explodes if you drop it into water. tree →
Atomic clocks use caesium to keep perfect time. tree →
Caesium's symbol is Cs. tree →
Caesium melts on a very hot day. tree →
Radioactive caesium spread after the nuclear accident. tree →

Note

UK spelling «caesium»; US spelling «cesium». Uncountable. Say it «SEE-zee-um». Safety: alkali metals are dangerous and only handled by trained scientists.

On Mova

Trees and pragmatics of «caesium» in the school dictionary: every meaning and example parsed by Mova, with its dependency tree and frames.
«caesium» in the school dictionary on Mova free.

This page in Markdown → https://md.dictionary.elamur.ai/free/en/english/caesium/