Ninety

Definition

Ninety is a cardinal number that represents the quantity equal to nine times ten (90). It is also used to denote the years between 90 and 99 in a person's life or a century.

Parts of Speech

• Noun
• Adjective

Pronunciation

American English

• IPA Pronunciation: /ˈnaɪn.ti/
• Respelling: NINE-tee

British English

• IPA Pronunciation: /ˈnaɪn.ti/
• Respelling: NINE-tee

Etymology

The word "ninety" originates from Old English "nigontig," which is a compound of "nigon" (nine) and "-tig" (a group of ten). It is derived from Proto-Germanic "*newuntigi" and Proto-Indo-European roots.

Derivatives

• Ninetieth (adjective, noun)
• Ninetyfold (adjective, rare)
• Ninety-something (noun, informal)
• Ninety-plus (adjective, informal)
• Ninety-year-old (noun/adjective)

Synonyms

• XC (Roman numeral)
• Nine tens
• Four score and ten (archaic)

Antonyms

• None

Usage

The term "ninety" is used in mathematics, chronological contexts, and everyday life. For example: "He scored ninety points on the test," or "She lived to the age of ninety."

Related Terms

• Number: A mathematical object used to count or measure.
• Decimal: A number system based on the number ten.
• Century: A period of 100 years.

Detailed Definitions

Noun

• The cardinal number 90: Represents the quantity equal to nine tens.
  • Example: "The price of the book is ninety dollars."
• A decade of life or years in a century: Refers to the 90s in age or a century.
  • Example: "The building was constructed in the ninety-ninth year of the 19th century."

Adjective

• Being 90 in number: Describes a total or quantity.
  • Example: "The school has ninety students enrolled."