Wisdom, perhaps of old people? (6)
I believe the answer is:
norman
'wisdom' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'of old people?' is the wordplay.
'of old' becomes 'nor' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'people?' becomes 'man' (I've seen this in other clues).
'nor'+'man'='NORMAN'
'perhaps' is the link.
Can you help me to learn more?
(Other definitions for norman that I've seen before include "Barry, Greg or Jessye" , "Ten sixty six invader" , "he invaded England" , "Like William the Conqueror?" , "Someone who's not British" .)