lestivo

Lestivo is a proposed grammatical category in linguistic theory. It designates a hypothetical mood or aspect used to encode precautionary action aimed at preventing a possible undesired outcome. The term blends the English conjunction "lest" with the suffix -ivo, following a common practice in linguistics of naming moods after functional semantics rather than traditional grammatical labels.

In the theoretical account, a sentence with lestivo marks indicates that the speaker's primary goal is to avert a potential event, rather than instantiate a wish, command, or factual state. The exact realizations vary: it could be a dedicated affix on the verb, a periphrastic construction, or a special clause linkage.

Attestation and status: Lestivo is not widely attested in natural languages. It appears in some discussions among typologists and in some constructed-language projects as a way to explore how precautionary semantics could be encoded. Critics argue it risks conflating purpose clauses with a distinct mood, and that cross-linguistic evidence is lacking.

Illustrative example (fictional): In a hypothetical language with lestivo marking on the verb, one might hear: "I leave-lestivo to avoid being late," meaning the action is taken specifically to prevent lateness.

Related topics include mood systems, the subjunctive, and the use of auxiliary constructions to express purpose or prevention.