The term that defines a behavior or trait of an organism that allows it to survive in its particular environment is adaptation.

Here's why:

* Adaptation refers to the process by which organisms evolve over time to become better suited to their environment. These adaptations can be physical traits (like camouflage or sharp claws) or behavioral traits (like migration or hibernation).

* Survival is the ability of an organism to stay alive and reproduce in its environment.

* Environment is the surroundings or conditions in which an organism lives.

Therefore, adaptation is the key factor that allows an organism to survive in its particular environment.