noun
1. : a common multiple of the denominators of a number of fractions
2.
a. : something that marks a group of things as alike or that characterizes a group or class : a trait or characteristic in common
the essence of religious experience, the actual common denominator of the world's great religions — H.J.Muller
diverse writings whose only common denominator was a supposed sophistication — J.D.Hart
the common denominator in this collection of distraught … men and women is that they are all Americans who are dissatisfied with their lives — Harrison Smith
b. : something on which all in a group may agree
trying to find a common denominator that would bring the opposing factions of the party together
c. : a strain, theme, quality, or trait persisting throughout a mass of material (as the writings of an author)
the common denominator, the atmosphere and the whole tempo of a writer's work may be recorded by just one sentence — Paul Potts