You don't. They're two separate folders so you need two separate operations... BUT, beware that move is a move, so what you need is a move AND a copy.
So you'd need TWO define.
define('UPLOAD_PATH_1','images/thumb/');
define('UPLOAD_PATH_2','images/other/');
and then the move AND a copy. I would not do the copy unless the move succeeded:
$status = move_uploaded_file($tmp, UPLOAD_PATH_1 . $name);
if ($status) {
copy(UPLOAD_PATH_1 . $name, UPLOAD_PATH_2 . $name);
Though I would be questioning why you'd want to waste disk space on two copies of the same file in a directory PHP (and therefor HTTP) has access to. link() might be a better choice than copy(), so there would in fact only one file and you are just creating virtual pointers to it -- but that would depend on your actual usage scenario.