action( 'woocommerce_after_subcategory_title', 'custom_add_product_description', 12);
function custom_add_product_description ($category) {
$cat_id        =    $category->term_id;
$prod_term    =    get_term($cat_id,'product_cat');
$description=    $prod_term->description;

echo '<div>'.$description.'</div>';
}