diff --git a/stdlib/array.mli b/stdlib/array.mli
index ddd27395c..10a71757e 100644
--- a/stdlib/array.mli
+++ b/stdlib/array.mli
@@ -127,7 +127,7 @@ val iter : ('a -> unit) -> 'a array -> unit
    the elements of [a].  It is equivalent to
    [f a.(0); f a.(1); ...; f a.(Array.length a - 1); ()]. *)
 
-val iter2 : ('a -> 'b -> 'c) -> 'a array -> 'b array -> unit
+val iter2 : ('a -> 'b -> unit) -> 'a array -> 'b array -> unit
 (** [Array.iter2 f a b] applies function [f] to all the elements of [a]
    and [b].
    Raise [Invalid_argument] if the arrays are not the same size. *)