WordWeight : Weighing the Words

Pronunciation : De*nom"i*na`tor
Part of Speech : n.
Etymology : [Cf. F. d?nominateur.]
Definition : 1. One who, or that which, gives a name; origin or source of a name. This opinion that Aram . . . was the father and denomination of the Syrians in general. Sir W. Raleigh.

2. (Arith.)

Defn: That number placed below the line in vulgar fractions which shows into how many parts the integer or unit is divided.

Note: Thus, in denominator, showing that the integer is divided into five parts; and the numerator, 3, shows how many parts are taken.

3. (Alg.)

Defn: That part of any expression under a fractional form which is situated below the horizontal line signifying division.

Note: In this sense, the denominator is not necessarily a number, but may be any expression, either positive or negative, real or imaginary. Davies & Peck (Math. Dict. )
Source : Webster's Unabridged Dictionary, 1913