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 really see how this works, but
'for' could be 'pro' (as in being 'pro' 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 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" .)