diff --git a/docs/grammar/README.md b/docs/grammar/README.md
index f8edf344cd..891e76c7fd 100644
Binary files a/docs/grammar/README.md and b/docs/grammar/README.md differ
diff --git a/docs/grammar/abnf-grammar.txt b/docs/grammar/abnf-grammar.txt
index 92a41f8474..5c409d61dc 100644
--- a/docs/grammar/abnf-grammar.txt
+++ b/docs/grammar/abnf-grammar.txt
@@ -69,6 +69,7 @@ keyword = %s"address"
         / %s"char"
         / %s"console"
         / %s"const"
+        / %s"constant"
         / %s"else"
         / %s"field"
         / %s"for"
@@ -317,7 +318,7 @@ function-declaration = %s"function" identifier
 
 function-parameters = function-parameter *( "," function-parameter ) [ "," ]
 
-function-parameter = [ %s"public" / %s"const" ] identifier ":" type
+function-parameter = [ %s"public" / %s"constant" ] identifier ":" type
 
 declaration = function-declaration