diff --git a/doc/manual/src/language/index.md b/doc/manual/src/language/index.md
index b4ffe171b..3ed00d8e3 100644
--- a/doc/manual/src/language/index.md
+++ b/doc/manual/src/language/index.md
@@ -104,6 +104,14 @@ the rest.
       A path relative to the file containing this Nix expression
     </td>
   </tr>
+  <tr>
+    <td>
+       <nixpkgs>
+    </td>
+    <td>
+      Search path. Value determined by [`$NIX_PATH` environment variable](../command-ref/env-common.md#env-NIX_PATH).
+    </td>
+  </tr>
   <tr>
     <td>
        *Compound values*