Eighteen

Definition

Eighteen is both a noun and an adjective. It refers to the number 18, which is the natural number following 17 and preceding 19. As an adjective, it is used to describe a quantity or grouping of eighteen items.

Parts of Speech

• Noun
• Adjective

Pronunciation

American English

• IPA Pronunciation: /ˌeɪˈtiːn/
• Respelling: ay-TEEN

British English

• IPA Pronunciation: /ˌeɪˈtiːn/
• Respelling: ay-TEEN

Etymology

The word "eighteen" originates from the Old English "eahta-tīene," meaning "eight-ten." This term follows the pattern of compound numbers in Germanic languages, combining "eight" and "ten" to signify the quantity of 18.

Derivatives

• Eighteenth (adjective/noun)
• Eighteens (plural noun, informal)
• Eighteenfold (adjective/adverb)
• Eighteen-year-old (noun/adjective)
• Eighteenth-century (adjective)

Synonyms

• XVIII (Roman numeral)
• Eight plus ten
• Two nines (informal)

Antonyms

• None

Usage

The term "eighteen" is used to denote the quantity 18, such as in "He turned eighteen today," or to count objects, as in "There are eighteen seats in the room."

Related Terms

• Number: A mathematical object used to count, measure, and label.
• Numeral: A symbol or group of symbols that represents a number.
• Count: The act of determining the total number of items.

Detailed Definitions

Noun

• The number 18: Refers to the natural number that comes after 17 and before 19.
  • Example: "Eighteen is considered an adult age in many countries."

Adjective

• Consisting of or relating to the number 18: Describes a quantity that includes or is comprised of eighteen units.
  • Example: "She baked eighteen cookies for the party."