from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A person 90 years old or between 90 and 100 years old.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. One who is between the age of 90 and 99, inclusive. One who is in his or her tenth decade.
- adj. Being between the age of 90 and 99, inclusive. In one's tenth decade.
- adj. Of or relating to a nonagenarian.
from the GNU version of the Collaborative International Dictionary of English
- n. A person ninety years old.
from The Century Dictionary and Cyclopedia
- Containing or pertaining to ninety.
- n. A person who is ninety years old.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. someone whose age is in the nineties
- adj. being from 90 to 99 years old
From Latin nōnāgēnārius, from nōnāgēnī, ninety each, from nōnāgintā, ninety : nōnus, ninth; see nona- + -gintā, ten times; see dekm̥ in Indo-European roots.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Latin nōnāgēnārius ("of the number ninety") (from nonageni ("ninety each"), from nonaginta ("ninety"), from nona- (akin to novem ("nine")) + -ginta (akin to viginti ("twenty")), + -arius) + -an (Wiktionary)