Formerly enough, for instance (7)
I believe the answer is:
example
'for instance' is the definition.
(synonyms)
'formerly enough' is the wordplay.
'formerly' becomes 'ex' (prefix meaning former or onetime).
'enough' becomes 'ample' (I've seen this in another clue).
'ex'+'ample'='EXAMPLE'
(Other definitions for example that I've seen before include "Typical specimen" , "Something illustrating a general rule" , "Fact that illustrates a general rule" , "Precedent" , "lesson" .)