Definition

1. Adjective:

   • Being from 90 to 99 years old: Describing a person whose age is between ninety and ninety-nine years.

2. Noun:

   • A person who is between 90 and 99 years old: Someone whose age is in their tenth decade of life.

Usage Examples

• Adjective:

  • The study focused on the health of nonagenarian patients.
  • She is a nonagenarian author who just published her latest novel.

• Noun:

  • My great-grandmother is a sprightly nonagenarian.
  • The community honored its nonagenarians with a special celebration.

Advanced Usage

• The term is often used in demographic, medical, and sociological contexts to describe a specific age cohort.
• It can be used attributively (e.g., ) or predictively (e.g., ).

Variants and Related Words

• Centenarian (noun/adjective): A person who is 100 years old or older.
• Octogenarian (noun/adjective): A person who is between 80 and 89 years old.
• Septuagenarian (noun/adjective): A person who is between 70 and 79 years old.

Synonyms

• Ninety-something (informal noun): A person in their nineties.
• In one's nineties (descriptive phrase): Being aged 90 to 99.

Antonyms

• Minor (noun): A person under the age of legal majority.
• Young adult (noun): A person in the early stage of adulthood.

Notes

• The word is derived from Latin , from (ninety each).
• It specifically denotes the decade from 90 to 99, distinct from a centenarian (100+).

Adjective

1. being from 90 to 99 years old
   • the nonagenarian inhabitants of the nursing home

Noun

1. someone whose age is in the nineties