non·a·ge·nar·i·an (nŏn′ə-jə-nârē-ən, nō′nə-)
A person 90 years old or between 90 and 100 years old.
[From Latin nōnāgēnārius, from nōnāgēnī, ninety each, from nōnāgintā, ninety : nōnus, ninth; see NONA- + -gintā, ten times; see dek in the Appendix of Indo-European roots.]
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