Swear copper succeeded framing son (4)
I believe the answer is:
cuss
'swear' is the definition.
(I've seen this before)
'copper succeeded framing son' is the wordplay.
'copper' becomes 'cu' (chemical symbol).
'succeeded' becomes 's' (genealogical abbreviation).
'framing' means one lot of letters goes inside another.
'son' becomes 's'.
'cu'+'s'='cus'
'cus' going around 's' is 'CUSS'.
(Other definitions for cuss that I've seen before include "Oath; (annoying sort of) person" , "Stubborn person" , "Use bad language (informal)" , "Swear (slang)" , "Blaspheme" .)