Iinfinitive

Iinfinitive is a term used in some linguistic discussions to denote a non-finite verb form that is related to the infinitive but is morphologically distinguished by a prefix or inflection designated as I-. The concept appears primarily in theoretical work or in discussions of constructed languages; it is not a universally recognized category in mainstream grammar.

In analyses that employ the term, the Iinfinitive behaves like an infinitive in forming non-finite clauses and in allowing complementation, but it may carry additional semantic or syntactic features. For example, some theories associate the Iinfinitive with irrealis mood, imperfectivity, or a particular aspectual nuance, making it distinct from the bare infinitive or to-infinitive.

Relation to other non-finite forms: The Iinfinitive is typically described as a subtype of non-finite verbs, alongside gerunds, infinitives, and converbal forms, differing in its morphological marking and sometimes in its distribution.

Attestation and usage: No widely spoken language is universally agreed to have a grammatically distinct Iinfinitive; references to it are concentrated in specialized linguistic literature, typological surveys, or fiction/conlang grammars. It may appear in cross-linguistic typologies as a theoretical construct or as a feature of constructed languages.

Etymology and terminology: The name derives from the proposed prefix I- that marks the form in some analyses.

Examples (hypothetical): In a prototypical language, the Iinfinitive of “to run” could be formed as I-run, used as the base form for non-finite clauses, contrasting with the bare infinitive run or the to-infinitive to run.