Unique (adjective)

1. Being the only one of its kind; unlike anything else.
2. Extraordinary; exceptional.

Origin:

Late middle english: from old french, or from latin unicus "one and only", from unus "one".

Examples:

1. The painting is a unique work of art.
2. The snowflake is a unique design.
3. She has a unique style.
4. He has a unique talent.
5. The experience was unique.