Changed some terms in a new deal (7)
I believe the answer is:
altered
'changed' is the definition.
('alter' can be a synonym of 'change')
'terms in a new deal' is the wordplay.
'terms' becomes 'ter' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'in' means one lot of letters goes inside another.
'a new' indicates an anagram.
'deal' with letters rearranged gives 'aled'.
'ter' going into 'aled' is 'ALTERED'.
'some' acts as a link.
Can you help me to learn more?
(Other definitions for altered that I've seen before include "Changed, adapted" , "Different" , "Change" , "Metamorphosed" , "Treadle (anag)" .)