Sticky solution to a clue, half-hidden in part of the orchard (7)
I believe the answer is:
treacle
'sticky solution' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'a clue half-hidden in part of the orchard' is the wordplay.
'half-hidden' means to take half the letters.
'in' is an insertion indicator.
'part of the orchard' becomes 'tree' (I can't explain this - if you can you should believe this answer much more).
'clue' cut in half is 'cl'.
'a'+'cl'='acl'
'acl' going into 'tree' is 'TREACLE'.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for treacle that I've seen before include "Sticky produce" , "well described by Dormouse" , "Sticky fluid" , "Syrup, molasses" , "Sweet, black viscous substance" .)