Those which some of the wise can be sat on (5)
I believe the answer is:
seats
'those which some' is the definition.
I can't tell whether this definition defines the answer.
'the wise can be sat on' is the wordplay.
'the wise' becomes 'se' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'can be' is an anagram indicator.
'on' is an insertion indicator (as in clothing \'on\' a person).
'sat' is an anagram of 'ats'.
'se' placed into 'ats' is 'SEATS'.
'of' is the link.
Can you help me to learn more?
(Other definitions for seats that I've seen before include "Parliamentary constituencies" , "Chairs, stools" .)