<p><strong>Adjective</strong></p><ul><li>Given or felt by each toward the other; mutual: reciprocal respect.</li><li>Given, performed, felt, etc., in return: reciprocal aid.</li><li>Matching; corresponding; equivalent: reciprocal privileges at other health clubs.</li><li>(Of a pronoun or verb) expressing mutual relationship or action: “Each other” and “one another” are reciprocal pronouns.</li><li>Inversely corresponding; opposing: reciprocal muscles in your back.</li><li>Mathematics: noting expressions, relations, etc., involving reciprocals: a reciprocal function.</li><li>Navigation: bearing in a direction 180° to a given direction; back.</li></ul><p><strong>Noun</strong></p><ul><li>Something that is reciprocal to something else: Faith and fear are reciprocals.</li><li>Also called multiplicative inverse.</li><li>Mathematics: the ratio of unity to a given quantity or expression; that by which the given quantity or expression is multiplied to produce unity: The reciprocal of x is 1/x.</li></ul>