Which interaction among species typically results in one benefiting at the expense of another?

The interaction that typically results in one species benefiting while another is harmed is parasitism. In this relationship, one organism, the parasite, lives on or in a host organism and derives nutrients at the host's expense. This often leads to negative effects on the host, which can include suffering, disease, or even death.

In contrast, mutualism involves both species benefiting from the interaction, while commensalism has one species benefiting and the other being unaffected. Symbiosis generally refers to close interactions between different species, which can include mutualism, commensalism, and parasitism among other forms. Therefore, parasitism is the distinct interaction where one organism benefits at a cost to another, fitting the description provided in the question.