(Definition of eighteenth from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)

Eighteenth definition: next after the seventeenth; being the ordinal number for 18.. See examples of EIGHTEENTH used in a sentence.

eighteenth (ˈeɪˈtiːnθ) adj (Mathematics) (usually prenominal) a. coming after the seventeenth in numbering or counting order, position, time, etc; being the ordinal number of eighteen: often written 18th

Nov 27, 2025 · eighteenth (plural eighteenths) The person or thing in the eighteenth position. One of eighteen equal parts of a whole. (informal) A party to celebrate an eighteenth birthday.

Definition of eighteenth noun in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

Eighteenth definition: The ordinal number matching the number 18 in a series.

WordReference Random House Unabridged Dictionary of American English © 2024 eight•eenth (ā′ tēnth′), adj. next after the seventeenth; being the ordinal number for 18. being one of 18 equal parts. …

Political boundaries at the beginning of year 1700 Storming of the Bastille, 14 July 1789, an iconic event of the French Revolution. Development of the Watt steam engine in the late 18th century was an …

The term "eighteenth" typically refers to the ordinal form of the number eighteen, indicating it as the 18th in a series or order. It could refer to the eighteenth day of a month, a person's eighteenth year …

eighteenth Other forms: eighteenthly; eighteenths Definitions of eighteenth adjective coming next after the seventeenth in position synonyms: 18th