owietleniu
Owietleniu is not a standard Polish word. It is typically encountered as a non-diacritic misspelling of oświetleniu, the dative or locative form of oświetlenie, meaning illumination or lighting. The root oświetl- comes from the verb oświetlić, “to illuminate.” The noun oświetlenie denotes the concept of lighting, infrastructure, or systems of illumination. The form oświetleniu appears in grammatical contexts such as “w oświetleniu ulicznym” (“in street lighting”) or “dla oświetleniu” (for illumination) depending on the sentence structure. When spelled as owietleniu, the word does not establish a separate semantic item and is not found in standard dictionaries.
In proper Polish, correct spelling should be chosen according to case: oświetlenie (nominative), oświetlenia (genitive), oświetleniu
See also: oświetlenie, oświetlić, oświetlacz, oświetlenie uliczne.