atom
Pronunciation:
/ˈatəm//ˈatəm/noun
Definitions
The smallest possible amount of matter which still retains its identity as a chemical element, now known to consist of a nucleus surrounded by electrons.
(history of science) A hypothetical particle posited by Greek philosophers as an ultimate and indivisible component of matter.
The smallest, indivisible constituent part or unit of something.
In logical atomism, a fundamental fact that cannot be further broken down.