diff --git a/python/polars_ds/extensions.py b/python/polars_ds/extensions.py
index c6d250f1..391ccd55 100644
--- a/python/polars_ds/extensions.py
+++ b/python/polars_ds/extensions.py
@@ -12,7 +12,7 @@ def __init__(self, expr: pl.Expr):
 
     def std_err(self, ddof: int = 1) -> pl.Expr:
         """
-        Returns the standard error of the variable.
+        Estimates the standard error for the mean of the expression.
         """
         return self._expr.std(ddof=ddof) / self._expr.count().sqrt()