n. 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.] non′a·ge·nari·an adj. |
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