diff --git a/maint_tools/test_docstrings.py b/maint_tools/test_docstrings.py
index 9b23b1789ae..940f00c7313 100644
--- a/maint_tools/test_docstrings.py
+++ b/maint_tools/test_docstrings.py
@@ -59,7 +59,6 @@ DOCSTRING_IGNORE_LIST = [
     "HistGradientBoostingRegressor",
     "HuberRegressor",
     "IncrementalPCA",
-    "IsolationForest",
     "Isomap",
     "IsotonicRegression",
     "IterativeImputer",
diff --git a/sklearn/base.py b/sklearn/base.py
index 9e762bc1cb7..552132c2512 100644
--- a/sklearn/base.py
+++ b/sklearn/base.py
@@ -789,8 +789,8 @@ class OutlierMixin:
 
         Parameters
         ----------
-        X : {array-like, sparse matrix, dataframe} of shape \
-            (n_samples, n_features)
+        X : {array-like, sparse matrix} of shape (n_samples, n_features)
+            The input samples.
 
         y : Ignored
             Not used, present for API consistency by convention.