Learning of WI's party ending in bedlam (6)
I believe the answer is:
wisdom
'learning' is the definition.
(thesaurus)
'wi's party ending in bedlam' is the wordplay.
'party' becomes 'do' (do is a kind of party).
'ending in' says to take the final letters.
The last letter of 'bedlam' is 'm'.
'wis'+'do'+'m'='WISDOM'
'of' is the link.
(Other definitions for wisdom that I've seen before include "Soundness of judgment, as taught by experience" , "Type of tooth" , "Accumulated experience and mature judgement" , "Sensible thinking" , "Put forward (an idea)" .)