equal vs reciprocal

equal

adj
  • The same in all respects. 

  • Intended for voices of one kind only, either all male or all female; not mixed. 

  • Adequate; sufficiently capable or qualified. 

  • Exactly identical, having the same value. 

verb
  • To make equivalent to; to cause to match. 

  • To have as its consequence. 

  • To be equal to, to have the same value as; to correspond to. 

noun
  • A person or thing of equal status to others. 

reciprocal

adj
  • Mutually interchangeable. 

  • Expressing mutual action, applied to pronouns and verbs; also in a broad sense: reflexive. 

  • Of a feeling, action or such: mutual, uniformly felt or done by each party towards the other or others; two-way. 

  • Done, given, felt, or owed in return 

  • Used to denote different kinds of mutual relation; often with reference to the substitution of reciprocals for given quantities. 

noun
  • A construction expressing mutual action. 

  • The number obtained by dividing 1 by another given number; the result of exchanging the numerator and the denominator of a fraction. 

How often have the words equal and reciprocal occurred in a corpus of books? (source: Google Ngram Viewer )