Nondescript (adjective)

1. Having no striking or distinctive characteristics; unremarkable.
2. Not easily classified or described; lacking distinctive qualities or features.

Origin:

From non- + descriptive, from the sense of "not having a distinctive or interesting appearance".

Examples:

1. The building was a nondescript gray structure, easily overlooked amidst the bustling city.
2. The movie was criticized for its dull, nondescript plot and lack of memorable characters.
3. The room was decorated in a plain, nondescript style, lacking any personal touches or unique features.
4. Despite its nondescript exterior, the restaurant was known for its exceptional cuisine.
5. The professor had a quiet, nondescript demeanor, but was widely respected for his vast knowledge and expertise.