Mistress Gwyn doesn’t finish fruit, cut beforehand with hooked implement (7)
I believe the answer is:
grapnel
'hooked implement' is the definition.
'grapnel' can be an answer for 'implement' (grapnel is a kind of implement). I am not certain of the 'hooked' bit.
'mistress gwyn doesn't finish fruit cut beforehand' is the wordplay.
'mistress gwyn' becomes 'nell' (I've seen this in another clue).
'doesn't finish' means to remove the last letter.
'fruit cut' becomes 'grap' (I can't justify this - if you can you should give a lot more credence to this answer).
'beforehand' means one lot of letters go next to another.
'nell' with its last letter removed is 'nel'.
'nel' after 'grap' is 'GRAPNEL'.
'with' is the link.
Can you help me to learn more?
(Other definitions for grapnel that I've seen before include "Grasping implement" , "Rope/hook device" , "Light anchor for small boats" , "Small anchor with three or four flukes" , "Hook on rope" .)