eighteenth eighteenth /ˈeɪˈtiːnθ/

adjective

1. () Coming next after the seventeenth in position  ( 18th , eighteenth )
   coming next after the seventeenth in position
    The eighteenth century was a time of great change
   The eighteenth century was a time of great change
   

noun

1. Position 18 in a countable series of things  ( eighteenth )
   position 18 in a countable series of things