Substitution of one thing for another; interchange.
The reversal of an electric current.
The change to a lesser penalty or punishment by the State
Substitution, as a means of discriminating between phonemes.
The process or habit of journeying to and from work on a regular basis; commuting.
Specifically, the substitution of one kind of payment for another, especially a switch to monetary payment from obligations of labour.
A reciprocal relationship.
A relation of mutual dependence or action or influence.
A reciprocal construction involves two noun phrases where each of the participants occupies both the role of agent and patient with respect to the other. see: Wikipedia:Reciprocal pronoun.
The characteristic of being reciprocal, e.g. of a relationship between people.
The mutual exchange of rights, privileges or obligations between nations. see: Wikipedia:Reciprocity (international relations).
The responses of individuals to the actions of others.