Numerator

·noun One who numbers.

II. Numerator ·noun The term in a fraction which indicates the number of fractional units that are taken.

numerator
nŭmĕrātor, ōris, m. [numero], a counter, numberer (late Lat.): numerator siderum, Aug. Conf. 5, 4...

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.