[n] an activity that varies from a norm or standard; "any variation in his routine was immediately reported"
[n] a difference between conflicting facts or claims or opinions; "a growing divergence of opinion"
[n] the quality of being subject to variation
[n] the second moment around the mean; the expected value of the square of the deviations of a random variable from its mean value
[n] discord that splits a group
[n] an event that departs from expectations