Definition:Elementary Event

Context
Probability Theory.

Definition
Let $$\mathcal E$$ be an experiment.

An elementary event of $$\mathcal E$$, often denoted $$\omega$$ (Greek lowercase "omega") is one of the elements of the sample space $$\Omega$$ (Greek capital "omega") of $$\mathcal E$$.

That is, an elementary event is one of the possible outcomes of $$\mathcal E$$.