Untie rivets moving installation (11)
I believe the answer is:
investiture
'installation' is the definition.
(investiture is a kind of installation)
'untie rivets moving' is the wordplay.
'moving' indicates anagramming the letters.
'untie'+'rivets'='untierivets'
'untierivets' with letters rearranged gives 'INVESTITURE'.
(Other definitions for investiture that I've seen before include "Ceremony of conferring honours of rank on a person" , "Ordination" , "Induction ceremony" .)