The term "var" is a modern English abbreviation, originating in the 20th century within technical fields such as mathematics, statistics, and computer programming. It is a clipped form of the word "variable," which itself derives from the Latin variabilis, meaning "changeable," from the verb variare, "to change." The logic of the abbreviation follows a common pattern in technical jargon, where the first syllable or a few letters of a longer, frequently used term are adopted for brevity and efficiency in communication. Thus, "var" carries the core conceptual meaning of its source—something that is subject to change or that represents an unspecified element—into a compact, functional unit within specialized discourse.

The word "var" is a simplex, formed by clipping from longer English words. It does not contain separable morphemes in its current, abbreviated form.