diff --git a/source/texk/web2c/luatexdir/luaffi/README b/source/texk/web2c/luatexdir/luaffi/README
index 8093da53c41891958ad7acc6911285a0345b41d0..bff350f6f64b667d076f98c36ece53cb71b5b58e 100644
--- a/source/texk/web2c/luatexdir/luaffi/README
+++ b/source/texk/web2c/luatexdir/luaffi/README
@@ -8,7 +8,7 @@ local info = [[
 The ffi module is available for:
  
     archictures       : ARCH_X86 and ARCH_X64,
-    operating systems : OS_CE, OS_WIN, OS_LINUX, OS BD and OS_POSIX
+    operating systems : OS_CE, OS_WIN, OS_LINUX, OS_BSD and OS_POSIX
 
 The ARM processor is currently not supported. There are subtle
 differences between this module and the one in luajitTeX