Contend with opinion (4)
I believe the answer is:
view
'opinion' is the definition.
(I know that opinion is a class)
'contend with' is the wordplay.
'contend' becomes 'vie' (synonyms).
'with' becomes 'w' (abbreviation).
'vie'+'w'='VIEW'
(Other definitions for view that I've seen before include "See" , "The range of the eye" , "What can be seen from a specified point" , "conviction" , "judgment" .)