Sweet and sour dip (4,4)
I believe the answer is:
acid drop
'dip' is the definition.
Both the answer and definition are singular nouns.
Maybe they are linked in a way I don't understand?
'sweet and sour' is the wordplay.
'sweet' becomes 'drop' (I've seen this before).
'and' is a charade indicator (letters next to each other).
'sour' becomes 'acid' (I've seen this in another clue).
'drop' after 'acid' is 'ACID DROP'.
Can you help me to learn more?
(Other definitions for acid drop that I've seen before include "Lemony candy" , "Sharp tasting boiled sweet" , "Boiled sweet with sharp taste" .)