Shame on you, seizing power — it's arrogant (6)
I believe the answer is:
uppity
'arrogant' is the definition.
(thesaurus)
'shame on you seizing power' is the wordplay.
'shame' becomes 'pity' ('pity' can be a synonym of 'shame').
'on' says to put letters next to each other.
'you' becomes 'u' (I've seen this in other clues**).
'seizing' means one lot of letters goes inside another.
'power' becomes 'p'.
'pity' after 'u' is 'upity'.
'upity' placed around 'p' is 'UPPITY'.
'it's' is the link.
(Other definitions for uppity that I've seen before include "Snobbish" , "Presumptuously arrogant" , "In need of slapping down?" , "Not easily persuaded" , "Self-important, arrogant" .)