Sick and dirty (3,6)
I believe the answer is:
off colour
This clue might be a double definition.
'sick' is the first definition.
(I've seen this before)
'dirty' is the second definition.
Both the answer and definition are adjectives.
Maybe there's an association between them I don't understand?
'and' is the link.
Can you help me to learn more?
(Other definitions for off colour that I've seen before include "green?" , "Slightly unwell" , "Unwell - risque" , "Sick" , "Not in the pink?" .)