eighteenth

[ ey-teenth ]

adjective
  1. next after the seventeenth; being the ordinal number for 18.

  2. being one of 18 equal parts.

noun
  1. an eighteenth part, especially of one (1/18).

  2. the eighteenth member of a series.

Origin of eighteenth

1
before 900; Middle English eightenthe, eightethe,Old English eahtatēotha.See eighteen + -th2

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How to use eighteenth in a sentence

  • Add these together, and we find that the wine was seven-eighteenths of total fluid, and therefore the water eleven-eighteenths.

    Amusements in Mathematics | Henry Ernest Dudeney
  • The faces of the volutes must recede from the edge of the abacus inwards by one and a half eighteenths of that same amount.

British Dictionary definitions for eighteenth

eighteenth

/ (ˈeɪˈtiːnθ) /


adjective
  1. (usually prenominal)

    • coming after the seventeenth in numbering or counting order, position, time, etc; being the ordinal number of eighteen: often written 18th

    • (as noun): come on the eighteenth

noun
    • one of 18 approximately equal parts of something

    • (as modifier): an eighteenth part

  1. the fraction that is equal to one divided by 18 (1/18)

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012