WordWeb Online

1. A variation that deviates from the standard or norm
   "the deviation from the mean";
   - divergence, departure, difference
    
2. (statistics) the difference between an observed value and the expected value of a variable or function
    
3. The error of a compass due to local magnetic disturbances
    
4. Deviate behaviour
   - deviance, deviancy
    
5. A turning aside (of your course, attention or concern)
   "a deviation from the main highway";
   - diversion, digression, deflection, deflexion [Brit], divagation

Derived forms: deviations

Type of: abnormality, erroneousness, error, fluctuation, irregularity, statistic, turn, turning, variation

Encyclopedia: Deviation