cor·re·la·tion (kôr′ə-lāshən, kŏr′-)
1. A relationship or connection between two things based on co-occurrence or pattern of change: a correlation between drug abuse and crime.
2. Statistics The tendency for two values or variables to change together, in either the same or opposite way: As cigarette smoking increases, so does the incidence of lung cancer, indicating a positive correlation.
3. An act of correlating or the condition of being correlated.
[Medieval Latin correlātiō, correlātiōn- : Latin com-, com- + Latin relātiō, relation, report (from relātus, past participle of referre, to carry back; see RELATE).]
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