billigsten
Billigsten is a form that appears to be the superlative of the Norwegian adjective billig, meaning the cheapest. In standard Norwegian, the language typically uses the forms billigst and billigste rather than billigsten. Specifically, billigst is the ordinary superlative used with an indefinite noun, while billigste is the definite form used when the noun is definite (for example, den billigste bilen – the cheapest car). The exact form billigsten is not considered standard in contemporary Bokmål or Nynorsk and is commonly regarded as nonstandard or dialectal, or the result of influence from closely related languages.
In everyday Norwegian, you would more commonly encounter: Dette tilbudet er billigst i butikken (This offer
Within the Scandinavian languages, related forms exist with slight variation. Swedish uses billigaste as the superlative,
Adjective inflection in Norwegian; Norwegian grammar; Comparative and superlative forms; Scandinavian languages.