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covariate

American  
[koh-vair-ee-it, ‑-eyt] / koʊˈvɛər i ɪt, ‑ˌeɪt /

noun

Statistics.
  1. a continuous control variable that is observed rather than manipulated but can affect the outcome of an experiment or study.

    You need to adjust for education level and other covariates in interpreting the results.


Etymology

Origin of covariate

First recorded in 1965–70; co- + variate