diff --git a/docs/grammar/abnf-grammar.txt b/docs/grammar/abnf-grammar.txt
index 2dbf54bf9f..941019111e 100644
--- a/docs/grammar/abnf-grammar.txt
+++ b/docs/grammar/abnf-grammar.txt
@@ -78,6 +78,7 @@ end-of-line-comment = "//" *not-line-feed-or-carriage-return
 
 keyword = %s"address"
         / %s"bool"
+        / %s"circuit"
         / %s"console"
         / %s"const"
         / %s"constant"
@@ -241,11 +242,17 @@ literal = atomic-literal / affine-group-literal
 
 group-literal = product-group-literal / affine-group-literal
 
-primary-expression = identifier
-                   / literal
+primary-expression = literal
+                   / variable-or-free-constant
+                   / associated-constant
                    / "(" expression ")"
                    / free-function-call
                    / static-function-call
+                   / circuit-expression
+
+variable-or-free-constant = identifier
+
+associated-constant = named-type "::" identifier
 
 free-function-call = identifier function-arguments
 
@@ -253,9 +260,19 @@ static-function-call = named-type "::" identifier function-arguments
 
 function-arguments = "(" [ expression *( "," expression ) [ "," ] ] ")"
 
+circuit-expression = identifier "{" [ circuit-component-initializer
+                                      *( "," circuit-component-initializer )
+                                      [ "," ] ] "}"
+
+circuit-component-initializer = identifier
+                              / identifier ":" expression
+
 postfix-expression = primary-expression
+                   / circuit-component-expression
                    / operator-call
 
+circuit-component-expression = postfix-expression "." identifier
+
 operator-call = unary-operator-call / binary-operator-call
 
 unary-operator-call = postfix-expression "." identifier "(" ")"
@@ -370,7 +387,14 @@ function-parameters = function-parameter *( "," function-parameter ) [ "," ]
 function-parameter = [ %s"public" / %s"constant" / %s"const" ]
                      identifier ":" type
 
+circuit-declaration = %s"circuit" "{" [ circuit-component-declaration
+                                        *( "," circuit-component-declaration )
+                                        [ "," ] ] "}"
+
+circuit-component-declaration = identifier ":" type
+
 declaration = function-declaration
+            / circuit-declaration
 
 file = *declaration