For a semi-detached, shows potential (7)
I believe the answer is:
promise
'potential' is the definition.
(I've seen this before)
'for a semi-detached' is the wordplay.
I cannot quite see how this works, but
'for' could be 'pro' (as in being 'pro' or in favour of something) and 'pro' is located in the answer.
an anagram of 'semi' is 'mise' which is within the answer.
No letters remain.
This explanation may well be incorrect...
'shows' is the link.
Can you help me to learn more?
(Other definitions for promise that I've seen before include "Hopeful sign" , "Cause for hope" , "Guarantee" , "Verbal or other commitment of one person to another" , "Oath" .)