Merge pull request scikit-learn#7217 from ClimbsRocks/patch-9

minor wording fix

Author: GaelVaroquaux

doc/modules/preprocessing.rst

@@ -16,7 +16,7 @@ Standardization, or mean removal and variance scaling
 =====================================================
 
 **Standardization** of datasets is a **common requirement for many
-machine learning estimators** implemented in the scikit; they might behave
+machine learning estimators** implemented in scikit-learn; they might behave
 badly if the individual features do not more or less look like standard
 normally distributed data: Gaussian with **zero mean and unit variance**.