Invariable nouns are nouns that have the same form for both singular and plural, un film, dei film ‘a film, some films’, or for both masculine and feminine, un artista, un’artista ‘an artist’. An invariable adjective is one that does not change form to agree with the noun, whether masculine or feminine, singular or plural: un vestito rosa ‘a pink dress’, una giacca rosa ‘a pink jacket’; dei pantaloni rosa ‘some pink trousers’; delle calze rosa ‘some pink stockings’.