Meaning : A reciprocal relation between two or more things.
Synonyms : correlativity
Meaning : A 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).
Example :
What is the correlation between those two variables?.
Synonyms : coefficient of correlation, correlation coefficient
Meaning : A 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.
Synonyms : correlational statistics