expression
untitled
Used for works (paintings, poems, songs, etc.) that have no title. Often seen in art catalogs or track listings.
この曲は題名なしのまま発表された。
This piece was released without a title.
展覧会には「題名なし」という作品がいくつかあった。
There were several works called 'Untitled' in the exhibition.
Synonymous; 無題 is more common in formal or literary contexts, while 題名なし is more descriptive and colloquial.
Compound of 題名 (title) + なし (without). The spelling 無し is an older kanji usage for なし.