Otherwise see Latin translation (4)
I believe the answer is:
else
'otherwise' is the definition.
(synonyms)
'see latin translation' is the wordplay.
'latin' becomes 'l'.
'translation' is an anagram indicator.
'see'+'l'='seel'
'seel' with letters rearranged gives 'ELSE'.
(Other definitions for else that I've seen before include "Adverb meaning if not, otherwise" , "Besides, otherwise" , "Eels (anag)" , "Other than (what is under consideration)" , "Alternatively" .)