nameless

An nameless thing or person has no particular name given to them.

When people talk about something being "nameless", they usually mean that it doesn't have an official title or label. For example, a new law might come into effect with no specific name attached to it, so it's just called the "new law". In literature and art, sometimes characters or things don't get names because the author or creator wants them to remain mysterious or unknown. You might also hear people describe a place as having many anonymous buildings or streets that seem nameless because they don't have any distinctive labels.