reversion
noun [ S or U ] uk/rɪˈvɜː.ʃən/ us/rɪˈvɝː.ʒən/
formal倒退；回复，回归
a change back to a previous and often worse condition
The new procedures are being seen as a reversion to old, inefficient ways of working. 采用新工序被视为是开历史倒车，是退回到那种效率低下的老路上去。
law specialized归还;物归原主
a return of something to its previous owner