a reciprocal relation between two or more things

having or involving or consisting of more than one part or entity or individual

- treble,
- fourfold,
- manifold,
- nine-fold,
- sevenfold,
- six-fold,
- octuple,
- doubled,
- dual,
- eight-fold,
- quaternate,
- sextuple,
- binary,
- twofold,
- two-fold,
- duplex,
- triune,
- seven-fold,
- fivefold,
- quadruple,
- threefold,
- eightfold,
- sixfold,
- ternary,
- triple,
- quadruplex,
- quadruplicate,
- ninefold,
- ten-fold,
- tenfold,
- aggregate,
- bigeminal,
- five-fold,
- septuple,
- denary,
- double,
- quintuple,
- nonuple,
- three-fold,
- quaternary,
- duple,
- triplex,
- four-fold,
- multiplex

a constant number that serves as a measure of some property or characteristic

- transmittance,
- reflectance,
- coefficient of expansion,
- constant,
- weight,
- reflection factor,
- coefficient of friction,
- expansivity,
- drag coefficient,
- coefficient of self induction,
- reflectivity,
- coefficient of viscosity,
- absorption coefficient,
- modulus,
- absolute viscosity,
- self-inductance,
- coefficient of drag,
- dynamic viscosity,
- coefficient of absorption,
- coefficient of reflection,
- weighting,
- transmission,
- absorptance,
- mutual inductance,
- coefficient of mutual induction

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)

- parametric statistic,
- product-moment correlation coefficient,
- split-half correlation,
- multiple correlation coefficient,
- correlation coefficient,
- tetrachoric correlation,
- coefficient of correlation,
- Pearson product-moment correlation coefficient,
- biserial correlation coefficient,
- biserial correlation,
- chance-half correlation,
- tetrachoric correlation coefficient

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

the product of a quantity by an integer

offering several alternative answers from which the correct one is to be chosen; or consisting of such questions