Based on the classification you've provided, "abiotic" would be the term that describes something that is not living. Abiotic factors refer to non-living chemical and physical components of the environment, such as water, sunlight, soil, and minerals.
Here’s a brief explanation of the other terms for context:
- Endemic: Refers to species that are native to and found only within a specific geographic area.
- Unique: This generally refers to something that is one of a kind and does not fit into categories.
- Biotic: Refers to living organisms and their interactions within an ecosystem.
In summary, the correct answer is abiotic.