Definition from Wiktionary, the free dictionary
Alternative forms 
From Old French variance.
- The act of varying or the state of being variable
- A difference between what is expected and what happens
- The state of differing or being in conflict
- A discrepancy, especially between two legal documents
- (statistics) The second central moment in probability
- (computing, programming) covariance and contravariance generally
The state of differing or being in conflict
The second central moment in probability
From Latin variantia.
variance m (plural variances)