filthier , filthiest
Something that is filthy is very dirty.
grimy
He never washed, and always wore a filthy old jacket.
他从不洗澡,而且总是穿着一件极脏的旧夹克。
If you describe something as filthy, you mean that you think it is morally very unpleasant and disgusting, sometimes in a sexual way.
Apparently, well known actors were at these filthy parties.
看来一些著名演员也参加了这些下流的聚会。