The numerator is the name for one of the two terms of a common fraction. The other term is called the denominator. The numerator is the "counting" number. It tells how many fractional parts in a whole or set have been counted.
"Numerator" also has other meanings. For example, it is the first term of a ratio expressed as a common fraction. Note that the numerator is always written above the fraction bar, and the value below the fraction bar is the denominator:
As can be seen above, 3 is the numerator, and 4 is the denominator.