ˈætəˌvɪzəm læps ˈlæpsɪŋ ɹiːˈɡɹɛʃən ɹɪˈlæps ɹɪˈvɜː(ɹ)səl ɹɪˈvɜːs ɹɪˈvɝs ɹɪˈvɜːʒən ˈθɹəʊ.bæk ˈθɹoʊ.bæk ˈtɜː(ɹ)nəˌɹaʊnd a failure to maintain a higher state returning to a former state turning in the opposite direction a reappearance of an earlier characteristic (genetics) a return to a normal phenotype (usually resulting from a second mutation) (law) an interest in an estate that reverts to the grantor (or their heirs) at the end of some period (e.g., the death of the grantee)