Arm one in society (6)
I believe the answer is:
member
'arm' is the definition.
(thesaurus)
'one in society' is the wordplay.
I cannot really understand how this works, but
'one' could be 'me' (a setter might use 'one' to humourously mean 'me') and 'me' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for member that I've seen before include "Limb; society joiner" , "constituent" , "One who has joined, eg, a society" , "Limb - person belonging to a group" , "A body part or kind of participant" .)