The word "unidentified" is often used to describe something or someone that is unknown or unfamiliar. However, there are many other synonyms that can be used to convey the same meaning, such as anonymous, nameless, unrecognizable, inconspicuous, faceless, and unfamiliar. These words can be particularly useful when describing items or individuals that are difficult to describe or distinguish from one another. For example, when describing an unknown object in the sky, the word "unidentified" might be used, but it could also be described as being indistinct, ambiguous, or unrecognizable. Choosing the right synonym can help to convey a more specific or nuanced meaning to your audience.