Mistake to eat a cut of lamb that's salty (8)
I believe the answer is:
brackish
'salty' is the definition.
(I've seen this before)
'mistake to eat a cut of lamb' is the wordplay.
'mistake' becomes 'bish' (term for a blunder or mistake).
'to eat' means one lot of letters goes inside another.
'a cut of lamb' becomes 'rack' (I can't explain this - if you can you should believe this answer much more).
'bish' placed around 'rack' is 'BRACKISH'.
'that's' acts as a link.
Can you help me to learn more?
(Other definitions for brackish that I've seen before include "Sightly salty, as in river estuaries" , "Rich bask in slightly salty water" , "Slightly briny" , "rather salty" , "unpalatable" .)