He foresees a hold-up before the reform (7)
I believe the answer is:
prophet
'he foresees a' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'hold-up before the reform' is the wordplay.
'hold up' becomes 'prop' (I've seen this in another clue).
'before' means one lot of letters go next to another.
'reform' indicates an anagram (letters in a new form).
'the' anagrammed gives 'het'.
'prop'+'het'='PROPHET'
Can you help me to learn more?
(Other definitions for prophet that I've seen before include "One who foretells the future as in the Bible" , "reader" , "Foreteller" , "Biblical seer" , "Prognosticator" .)