Have yen for sage? Me too (8)
I believe the answer is:
likewise
'me too' is the definition.
(I've seen this in another clue)
'have yen for sage?' is the wordplay.
'have yen' becomes 'like' (I am not sure about this - if you are sure you should believe this answer much more).
'for' means one lot of letters go next to another.
'sage?' becomes 'wise' (similar in meaning).
'like'+'wise'='LIKEWISE'
Can you help me to learn more?
(Other definitions for likewise that I've seen before include "In similar way" , "In addition, similarly" , "Ditto, similarly" , "In similar manner" , "Similarly, moreover" .)