Rejected pound coin is forged, reveals inventor (7)
I believe the answer is:
marconi
'inventor' is the definition.
(I've seen this before)
'rejected pound coin is forged' is the wordplay.
'rejected' is a reversal indicator.
'pound' becomes 'ram' (synonyms).
'is forged' indicates anagramming the letters.
'ram' back-to-front is 'mar'.
'coin' is an anagram of 'coni'.
'mar'+'coni'='MARCONI'
'reveals' is the link.
(Other definitions for marconi that I've seen before include "Inventor of radio-telegraphy" , "Developer of radio telegraphy" , "Wireless inventor from Minorca" , "Italian inventor of radio" , "Nobel prizewinner" .)