Wine left outside home? Blow that! (8)
I believe the answer is:
clarinet
'blow that' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'wine left outside home?' is the wordplay.
'wine left' becomes 'claret' (claret is a kind of wine. I am not sure about the 'left' bit.).
'outside' is an insertion indicator (some letters go outside others).
'home?' becomes 'in' (to be in is to be (at) home).
'claret' going around 'in' is 'CLARINET'.
Can you help me to learn more?
(Other definitions for clarinet that I've seen before include "Single reed woodwind instrument" , "Find an instrument in claret" , "Music-maker" , "Woodwind instrument - Artie Shaw played one" , "Instrument in claret, strangely" .)