diff --git a/ext/gmp/gen/README.md b/ext/gmp/gen/README.md
index 836e13e2da..6228292b1b 100644
--- a/ext/gmp/gen/README.md
+++ b/ext/gmp/gen/README.md
@@ -2,7 +2,7 @@
 
 To generate these, first run the `./configure` script under the unpacked GMP dependency directory with the following options:
 
-maoOS:
+macOS:
 ```terminal
 ./configure --with-pic --disable-shared
 ```