diff --git a/src/transform/renamer.cc b/src/transform/renamer.cc
index 956d4076ce..d3d0cf9964 100644
--- a/src/transform/renamer.cc
+++ b/src/transform/renamer.cc
@@ -745,6 +745,7 @@ const char* kReservedKeywordsMSL[] = {
     "long3",
     "long4",
     "main",
+    "matrix",
     "metal",
     "mutable",
     "namespace",
diff --git a/src/transform/renamer_test.cc b/src/transform/renamer_test.cc
index 9b9ff3f274..2b07a39e74 100644
--- a/src/transform/renamer_test.cc
+++ b/src/transform/renamer_test.cc
@@ -1045,6 +1045,7 @@ INSTANTIATE_TEST_SUITE_P(
         "long3",
         "long4",
         "main",   // No functions called main
+        "matrix",
         "metal",  // The namespace
         "packed_bool2",
         "packed_bool3",