NONAGENARIAN

[no.na.ge.nar.i.an] n [L nonagenarius containing ninety, fr. nonageni ninety each, fr. nonaginta ninety, fr. nona- (akin to novem nine) + -ginta (akin to viginti twenty)--more at nine, vigesimal] (1804): a person whose age is in the nineties -- nonagenarian adj