Variance

n. act or instance of variation; divergence; discrepancy, strife, discord

In probability theory and statistics, the variance of a random variable (or somewhat more precisely, of a probability distribution) is one measure of statistical dispersion, averaging the squared distance of its possible values from the expected value. Whereas the mean is a way to describe the location of a distribution, the variance is a way to capture its scale or degree of being spread out. The unit of variance is the square of the unit of the original variable. The square root of the variance, called the standard deviation, has the same units as the original variable and can be easier to interpret for this reason.
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Noun
1. an event that departs from expectations
(synonym) discrepancy, variant
(hypernym) deviation, divergence, departure, difference
2. discord that splits a group
(synonym) division
(hypernym) discord, dissension
3. the second moment around the mean; the expected value of the square of the deviations of a random variable from its mean value
(hypernym) moment
(hyponym) standard deviation
(classification) statistics
4. a difference between conflicting facts or claims or opinions; "a growing divergence of opinion"
(synonym) discrepancy, disagreement, divergence
(hypernym) difference
(hyponym) allowance, leeway, margin, tolerance
5. the quality of being subject to variation
(synonym) variability, variableness
(hypernym) changeableness, changeability
(hyponym) variedness
6. an activity that varies from a norm or standard; "any variation in his routine was immediately reported"
(synonym) variation
(hypernym) activity
(derivation) deviate, vary, diverge, depart

n. variance, divergence

(n.)
The quality or state of being variant; change of condition; variation.
  

(n.)
Difference that produce dispute or controversy; disagreement; dissension; discord; dispute; quarrel.
  

(n.)
A disagreement or difference between two parts of the same legal proceeding, which, to be effectual, ought to agree, -- as between the writ and the declaration, or between the allegation and the proof.