Sure is. Use the code below in your theme functions.php file. I also included conditionals here as well in case someone wants to exclude something based on that. The first $exclude sets the global settings (these categories will be excluded always - cat-slug1, cat-slug2), and the others push additional variables onto $exclude in certain scenarios. You don't need the conditional lines, but I did, so I thought I'd share them.
// Exclude selective categories from the_category - GLOBAL SETTINGS
function the_category_filter($thelist,$separator=' ') {
if(!defined('WP_ADMIN')) {
//list the category names to exclude
$exclude = array('cat-slug1','cat-slug2');
if(is_category('2')) {
array_push($exclude,'cat-slug3','cat-slug4'); }
if(is_category('3')) {
array_push($exclude,'cat-slug5'); }
$cats = explode($separator,$thelist);
$newlist = array();
foreach($cats as $cat) {
$catname = trim(strip_tags($cat));
if(!in_array($catname,$exclude))
$newlist[] = $cat;
}
return implode($separator,$newlist);
} else
return $thelist;
}
add_filter('the_category','the_category_filter',10,2);
Much credit to Nick for help on this.