Soak? That's about right (5)
I believe the answer is:
drunk
'soak?' is the definition.
(thesaurus)
'about right' is the wordplay.
I cannot quite see how this works, but
'right' could be 'r' (common abbreviation) and 'r' is found within the answer.
The remaining letters 'dunk' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'that's' acts as a link.
Can you help me to learn more?
(Other definitions for drunk that I've seen before include "Nine Ac" , "Wino" , "Pickled (sl.)" , "Toper" , "Inebriated" .)