Otherwise a noted school of economics (4)
I believe the answer is:
else
'otherwise' is the definition.
(synonyms)
'a noted school of economics' is the wordplay.
I cannot quite see how this works, but
'school' could be 'lse' (London School of Economics) and 'lse' is located in the answer.
A single letter 'e' remains which might be clued in a way I don't understand.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for else that I've seen before include "Eels (anag)" , "Other than (what is under consideration)" , "As an alternative" , "Otherwise; different from" , "Besides, otherwise" .)