Infekcyjnej

Infekcyjnej is a grammatical form of the Polish adjective infekcyjny, meaning infectious or contagious. It is the feminine singular form used in several cases: genitive, dative, and locative. This contrasts with infekcyjna (nominative feminine), infekcyjnego (masculine or neuter/genitive), and other endings that agree with the noun they modify.

In practical terms, infekcyjnej appears when the feminine noun it describes is in a dependent case. Examples:

- choroby infekcyjnej – of an infectious disease (genitive singular)

- chorobie infekcyjnej – to/for an infectious disease (dative singular)

- o infekcyjnej chorobie – about an infectious disease (locative singular)

These forms are common in medical and scientific writing, as well as in descriptive text discussing infections and related topics.

Semantic notes indicate that infekcyjny and infekcyjny-related forms are often used as formal or technical alternatives to zakaźny, which more commonly denotes contagiousness in everyday language. While both terms describe spread by infection, infekcyjny tends to appear in clinical, laboratory, or epidemiological contexts, whereas zakaźny might be preferred in general communication about contagious diseases.

Etymology-wise, infekcyjny derives from infekcja (infection), itself from Latin infectio, through Polish linguistic development of medical terminology. The feminine endings, including infekcyjnej, reflect standard Polish adjective declension, ensuring agreement with feminine nouns such as choroba, infekcja, or tkanka.

Overall, infekcyjnej is a typical inflected form used to grammatically modify feminine nouns in contexts related to infection, most often encountered in formal medical or scientific Polish.