Open English Wordnet
Nouns
(n)correlation coefficient, coefficient of correlation, correlationa statistic representing how closely two variables co-vary; it can vary from -1 (perfect negative correlation) through 0 (no correlation) to +1 (perfect positive correlation)“what is the correlation between those two variables?”
(n)correlation, correlational statisticsa statistical relation between two or more variables such that systematic changes in the value of one variable are accompanied by systematic changes in the other