Filthy is one of the F words. However, it is acceptable to use in mixed company, and in G rated movies because it has six letters. Filthy is ambiguous. You can use it in a positive sense “I have been working in the garden, and got filthy.” That is good because you were productive. On the other hand “The kitchen is filthy” is bad because someone has been non-productive and too lazy to clean up.

via Daily Prompt: Filthy