Formerly plentiful for a typical case (7)
I believe the answer is:
example
'a typical case' is the definition.
'example' can be an answer for 'case' (I've seen this before). I'm not certain of the 'a typical' bit.
'formerly plentiful' is the wordplay.
'formerly' becomes 'ex' (prefix meaning former or onetime).
'plentiful' becomes 'ample' (synonyms).
'ex'+'ample'='EXAMPLE'
'for' is the link.
Can you help me to learn more?
(Other definitions for example that I've seen before include "Illustration or model" , "Something to be imitated" , "Specimen, sample" , "Illustrative exercise" , "Characteristic item" .)