General terms:
* Gesamtkunstwerk: This literally means "total work of art" and refers to a work that integrates multiple art forms, like opera or Wagner's concept.
* Werk: This simply means "work" and can be used for any type of artwork, from paintings to sculptures to literature.
* Kunstwerk: This means "artwork" and is a more formal term for a work of art.
Specific terms:
* Gemälde: This refers specifically to a painting.
* Skulptur: This refers to a sculpture.
* Buch: This refers to a book.
* Film: This refers to a film.
* Komposition: This refers to a musical composition.
The most appropriate word will depend on the specific artwork and the context of the discussion.
Example:
If you're talking about the complete body of work of a painter, you could say "das gesamte Werk von [Name des Künstlers]" (the entire work of [artist's name]).
If you're talking about a single painting, you could say "das Gemälde von [Name des Künstlers]" (the painting by [artist's name]).