/ Thesaurus / C Synonyms of constant of proportionality Find synonyms for: Noun1. factor of proportionality, constant of proportionality, factor, constantusage: the constant value of the ratio of two proportional quantities x and y; usually written y = kx, where k is the factor of proportionalityWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: profiterole Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language