Teams that can't be taken objectively (5)
I believe the answer is:
sides
'teams' is the definition.
(eg football sides)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for sides that I've seen before include "More than one team" , "Flanks, or opposing teams" , "Angles" , "Outer edges, left and right" , "opponents?" .)