Reciprocity

Webster's Dictionary

(1): ( n.) Reciprocal advantages, obligations, or rights; reciprocation.

(2): ( n.) Mutual action and reaction.

The Nuttall Encyclopedia

A term used in economics to describe commercial treaties entered into by two countries, by which it is agreed that, while a strictly protective tariff is maintained as regards other countries, certain articles shall be allowed to pass between the two contracting countries free of or with only light duties; this is the cardinal principle of Fair Trade, and is so far opposed to Free Trade.