English · Science & Technology
atom
/ˈæt.əm/
[/ˈæt.əm/]
basic unit of matter
Intermediatenoun
Definition
The smallest unit of a chemical element, made of a nucleus surrounded by electrons.
Example
Everything around us, from water to metal, is made of incredibly tiny particles called atoms.
Everything around us, from water to metal, is made of incredibly tiny particles called atoms.
Etymology
From Greek 'atomos' (indivisible), from 'a-' (not) plus 'tomos' (cut), via Latin 'atomus'.
How & Where It’s Used
A fundamental concept in chemistry and physics.