Akademik

reciprocal
1. adjective
a) Of a feeling, action or such: mutual, uniformly felt or done by each party towards the other or others; two-way.
b) Something that is contrary or opposite.
Syn: mutual, two-way, contrary, opposite, converse, inverse, inverted, cross
See Also: reciprocity
2. noun
Of a number, the number obtained by dividing 1 by the given number; the result of exchanging the numerator and the denominator of a fraction.

0.5 is the reciprocal of 2.

Syn: multiplicative, inverse

Wikipedia foundation.