inaktiivses

Inaktiivses is the Estonian inessive singular form of the adjective inaktiivne, used to describe something that is in an inactive state. The inessive case expresses a state or location within something and is commonly translated as "in" or "in the state of" in English. Therefore, inaktiivses describes a noun that is currently inactive, as in phrases like inaktiivses olekus olevad molekulid (molecules that are in an inactive state).

The word is formed from the root inaktiivne (inactive) with the Estonian adjective endings. Like other Estonian adjectives, its form changes according to number and case, so other inflected forms exist for plural nouns and for other grammatical roles in a sentence. In practice, inaktiivses appears primarily in descriptive, technical, or scientific prose to indicate a condition of inactivity rather than a general, persistent trait.

Etymology traces the term to the prefix in- meaning not and the root aktiivne meaning active, combined with the standard Estonian adjective suffixes. The concept parallels related terms such as aktiivne (active) and inactivity (inaktiivsus), and it is used to distinguish states of activity from states of non-activity in discussions of processes, reactions, or behaviors.

In use, inaktiivses denotes a temporary or contextual state rather than an absolute property. Its precise form depends on the noun it modifies and the sentence’s grammatical requirements. See also inactivity, Estonian grammar, inessive case.