Kitchen device imbecile partner ruined initially (5,8)
I believe the answer is:
lemon squeezer
'imbecile partner ruined initially' is the definition.
I can't tell whether this defines the answer.
'kitchen device' is the wordplay.
I cannot really see how this works, but
'kitchen device' could be 'squeezer' (I've seen this in another clue) and 'squeezer' is found in the answer.
The remaining letters 'lemon' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for lemon squeezer that I've seen before include "Juicer for citrus fruit" , "produces juicy stuff" , "Kitchen utensil" , "Device for extracting juice" .)