An interaction where one species is harmed while the other is unaffected is called

The interaction you are referring to is known as "amensalism." In amensalism, one species experiences a negative effect, while the other species remains unaffected by the interaction. This type of relationship can occur in various ecological contexts, such as competition for resources, where one species may inhibit the growth of another through the release of chemicals (allelopathy) or through physical means, while the other species does not gain any benefit from this interaction.

Amensalism is distinct from other ecological interactions such as predation, where one species benefits at the expense of another, and mutualism, where both species benefit. Understanding this relationship is important in ecology and helps explain community dynamics and species interactions within ecosystems.