ratio

n. proportional relation, relationship of quantity or size between two things

A ratio is a quantity that denotes the proportional amount or magnitude of one quantity relative to another.Ratios are unitless when they relate quantities of the same dimension. When the two quantities being compared are of different types, the units are the first quantity "per" unit of the second — for example, a speed or  velocity can be expressed in "miles per hour". If the second unit is a measure of time, we call this type of ratio a rate.
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Noun
1. the relative magnitudes of two quantities (usually expressed as a quotient)
(hypernym) magnitude relation, quantitative relation
(hyponym) margin of profit, profit margin, gross margin

n. reason, cause, basis for action

n. ratio, proportional relation, relationship of quantity or size between two things