diff --git a/src/textual/geometry.py b/src/textual/geometry.py
index d228391bb..32dbd0a7d 100644
--- a/src/textual/geometry.py
+++ b/src/textual/geometry.py
@@ -839,7 +839,7 @@ class Region(NamedTuple):
 
     @lru_cache(maxsize=1024)
     def split_horizontal(self, cut: int) -> tuple[Region, Region]:
-        """Split a region in to two, from a given x offset.
+        """Split a region in to two, from a given y offset.
 
         ```
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