discrete variable

A variable that is expressed in whole units or mutually exclusive categories. Whole numbers and category designations such as sex and marital status are examples of discrete data.

A variable which is broken down into separate size categories where no fractions are possible. For example, the number of cars travelling to a town can only be expressed in whole numbers: fractions cannot exist.

In quantitative research there are two broad types of variable: discrete and continuous. Discrete, or categorical, variables are those for which subjects or observations can be categorized. For example, vote choice is a discrete variable since there is a limited set of parties or candidates to vote for.

— Stephen Fisher