diff --git a/docs/docs/term_index.xml b/docs/docs/term_index.xml
index 48479149e..a30560aff 100644
--- a/docs/docs/term_index.xml
+++ b/docs/docs/term_index.xml
@@ -1296,6 +1296,7 @@
          <term file="imaging.html" name="scan_image_movable_parts" include="dlib/image_processing.h"/>
          <term file="imaging.html" name="find_points_above_thresh" include="dlib/image_processing.h"/>
 
+         <term file="dlib/image_processing/scan_fhog_pyramid_abstract.h.html" name="default_fhog_feature_extractor" include="dlib/image_processing.h"/>
          <term file="dlib/image_processing/scan_fhog_pyramid_abstract.h.html" name="num_separable_filters" include="dlib/image_processing.h"/>
          <term file="dlib/image_processing/scan_fhog_pyramid_abstract.h.html" name="threshold_filter_singular_values" include="dlib/image_processing.h"/>
          <term file="imaging.html" name="scan_fhog_pyramid"                      include="dlib/image_processing.h"/>