Peculiar (adjective)

1. Strange or unusual in a way that is difficult to describe or understand.
2. Not typical, normal, or ordinary; unique or unusual.
3. Particular to a particular person or thing; distinct or special.

Origin:

From the latin peculiaris "belonging to a private individual, individual".

Examples:

1. The peculiar smell of the chemical made it easy to identify.
2. His peculiar way of speaking made him stand out.
3. The peculiar behavior of the animal caught the attention of the scientists.
4. She had a peculiar habit of tapping her foot when she was thinking.
5. He had a peculiar talent for solving puzzles.