Taxonomy Term's Description

Got it.

I added a couple of lines to the last function theme_taxonomygroup_term , here's the code below.

/**
 * Theme a list of nodes associated with a term.
 * @param array $termlist array(node1, node2, ...)
 * @param string $term The name of the taxonomy term.
 * @param boolean $teaser Are we printing full nodes (t) or teasers (f)?
 */
function theme_taxonomygroup_term($termlist, $term, $teaser=false) {
  $descArray = taxonomy_get_term_by_name($term);
  $desc = $descArray[0]->description;
  $output = "";
  $output .= "<div id=\"taxonomygroup-{$term}-header\" class=\"taxonomygroup-header taxonomygroup-{$term}-header\">{$term}</div>";
  $output .= "<div class=\"taxonomygroup-descriptions\"><div class=\"taxonomygroup-{$term}-description\">" . $desc . "</div></div>";
  $output .= "<div class=\"taxonomygroup-content taxonomygroup-{$term}-content\">";
  foreach ($termlist as $node) {
    $output .= node_view($node, $teaser, false, true);
  } // foreach month
  $output .= "</div>";
  return $output;
} // function theme_taxonomygroup_term