Symbiosis, an interaction between two organisms living together in more or less intimate association.

Ethic of reciprocity, a general philosophical principle of most philosophies and religions.

Reciprocity (electromagnetism), theorems relating sources and the resulting fields in classical electromagnetism.

Reciprocity (photography), the relationship between the intensity of the light and duration of the exposure that result in identical exposure.

Serial reciprocity, where the benefactor of a gift or service will in turn provide benefits to a third party.

Reciprocity (evolution), mechanisms for the evolution of cooperation.

Reciprocity (cultural anthropology) and in relation to non-market economic exchange

Reciprocity (Canadian politics), 19th Century concept of free trade with the United States of America.

Reciprocity (social psychology), in-kind positive or negative responses of individuals towards the actions of others.

Reciprocity norm (negotiation)

Reciprocity (international relations), a principle that favours, benefits, or penalties that are granted by one state to the citizens or legal entities of another, should be returned in kind.

Traffic Violations Reciprocity where non-resident drivers are treated like residents.

Reciprocal may refer to: Reciprocal (mathematics), the number 1/x, which multiplied by x gives the product 1 Reciprocal rule, a technique in calculus for calculating derivatives of reciprocal functions Reciprocal lattice, a basis for the dual space of...

Reciprocity (mathematics)