* Synthetic: This is a general term for something that is made by humans, not found in nature.
* Artificial: Similar to synthetic, but can sometimes imply a more complex or manufactured process.
* Man-made: This emphasizes human creation.
* Unnatural: This implies a deviation from what is considered natural, but can be subjective depending on the specific context.
* Non-native: This is used to describe species that are not originally from a particular area.
Examples:
* Synthetic diamonds are not found naturally.
* Artificial sweeteners are made in a lab, not found in nature.
* Man-made polymers are not found naturally.
* Unnatural selection is a process that does not occur naturally.
* Non-native plants are introduced to a new area by humans.
The best word to use will depend on the specific context of your sentence.
