diff --git a/modules/taxonomy/taxonomy.module b/modules/taxonomy/taxonomy.module
index 2aa55a84cc9055398c873080c42b89018d82204b..db41a71a8ee9eb89d0baa218be25dbd9fa5abb48 100644
--- a/modules/taxonomy/taxonomy.module
+++ b/modules/taxonomy/taxonomy.module
@@ -380,7 +380,26 @@ function taxonomy_admin_vocabulary_title_callback($vocabulary) {
 }
 
 /**
- * Save a vocabulary given a vocabulary object.
+ * Saves a vocabulary.
+ *
+ * @param $vocabulary
+ *   A vocabulary object with the following properties:
+ *   - vid: The ID of the vocabulary.
+ *   - name: The human-readable name of the vocabulary.
+ *   - machine_name: The machine name of the vocabulary.
+ *   - description: (optional) The vocabulary's description.
+ *   - hierarchy: The hierarchy level of the vocabulary.
+ *   - module: (optional) The module altering the vocabulary.
+ *   - weight: (optional) The weight of this vocabulary in relation to other
+ *     vocabularies.
+ *   - original: (optional) The original vocabulary object before any changes
+ *     are applied.
+ *   - old_machine_name: (optional) The original machine name of the
+ *     vocabulary.
+ *
+ * @return
+ *   Status constant indicating whether the vocabulary was inserted (SAVED_NEW)
+ *   or updated(SAVED_UPDATED).
  */
 function taxonomy_vocabulary_save($vocabulary) {
   // Prevent leading and trailing spaces in vocabulary names.