Cut down a middle eight (7)
I believe the answer is:
abridge
'cut down' is the definition.
(I've seen this before)
'a middle eight' is the wordplay.
I cannot quite understand how this works, but
'a' is within the answer.
The remaining letters 'bridge' 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 abridge that I've seen before include "Curtail" , "Tighten up" , "Concentrate" , "trim" , "Cut short" .)