The term "Untitled" refers to something that does not have a name or title. It could be an artwork, song, book, movie, etc., which has not been given a specific name by its creator or owner.
And again, no surprise, these experiments begin to resemble figures, notably in Untitled 1962. (hamptonsarthub.com)
Although often described as monumental, his 15 untitled works in concrete actually seem modest in this enormous landscape. (bombmagazine.org)
With no required distinction between the realistic and abstract forms, one untitled painting on display combines clean, curved lines with a representational rendering of the rear end of a horse. (artobserved.com)