| Term | Definition |
| Mutualism | Both organisms benefit by their relationship with each other |
| Symbiosis | Another word for mutalism |
| Commensalism | One species benefits while the other is unaffected |
| Amensalism | One species is harmed while the other is unaffected |
| Competition | When different animals or plants fight for the same resources |
| Exploitation | One species benefits while the other is harmed |
| Predation | One species kills the other for food |
| Herbivory | When one species eats another, making it smaller |
| Parasitism | When an organism lives in or on another organism from which it obtains nutriments |
| Parasite | An organism that lives in or on a host |
| Host | A parasite lives in or on a ____ |
| Parasitoid | A parasite that kills their host is called a __________ |