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 understand 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 located in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'shows' acts as a 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" .)