läpäistyn

Läpäistyn is the genitive singular form of the Finnish past participle läpäisty, which comes from the verb läpäistä meaning to pass through, permeate, or pierce. As an adjective or participle, läpäisty describes something that has been penetrated or permeated. The form läpäistyn is used when the noun it modifies is in the genitive case, for example in phrases like läpäistyn katon tiiveys (the tightness of the penetrated roof) or läpäistyn rakennuksen rakenne (the structure of the penetrated building).

In practice, läpäisty functions as a past participle indicating a state resulting from an action. When describing a subject, the predicative form is typically läpäisty, as in Se on läpäisty (It is penetrated). The attributive form läpäistyn is therefore primarily seen in contexts where a noun is part of a genitive construction or a noun phrase describing possession or relation to the penetrated item.

Etymology and related forms: läpäistyn derives from läpäistä, with the standard Finnish past participle stem läpäist-, and the genitive singular suffix -yn used for adjectives and participles governing a genitive noun. Related words include läpäisy (permeation, penetration), läpäistä (to permeate, to pass through), and various inflected forms used in different grammatical cases.

Because läpäistyn is a grammatical inflection rather than a standalone lexical entry, its primary function is to enable precise, genitive-based attribution in technical or descriptive Finnish prose.