exclude categories in a query string?

Hi guys,

I know you can set a query string to show what categories you want to display – &taxonomy=listing&term=cat1,cat2,cat3 etc

Is there a way to exclude specific categories instead?

I only need to remove 1 in this case.

I’ve tried various different combinations by adding &exclude then the rest of the string but have had no luck.

Thanks in advance
Chris