diff --git a/src/wp-includes/post-template.php b/src/wp-includes/post-template.php
index 66517b1c91..59e4a50370 100644
--- a/src/wp-includes/post-template.php
+++ b/src/wp-includes/post-template.php
@@ -1439,7 +1439,8 @@ function wp_get_attachment_link( $id = 0, $size = 'thumbnail', $permalink = fals
 	 *
 	 * @param string      $link_html The page link HTML output.
 	 * @param int         $id        Post ID.
-	 * @param string      $size      Image size. Default 'thumbnail'.
+	 * @param string|array $size     Size of the image. Image size or array of width and height values (in that order).
+	 *                               Default 'thumbnail'.
 	 * @param bool        $permalink Whether to add permalink to image. Default false.
 	 * @param bool        $icon      Whether to include an icon. Default false.
 	 * @param string|bool $text      If string, will be link text. Default false.