Eighteenth

from WordNet (r) 3.0 (2006)
eighteenth
    adj 1: coming next after the seventeenth in position [syn:
           {eighteenth}, {18th}]
    n 1: position 18 in a countable series of things
    
from The Collaborative International Dictionary of English v.0.48
Eighteenth \Eight"eenth`\, a. [From {Eighteen}.]
   1. Next in order after the seventeenth.
      [1913 Webster]

   2. Consisting of one of eighteen equal parts or divisions of
      a thing.
      [1913 Webster]
    
from The Collaborative International Dictionary of English v.0.48
Eighteenth \Eight"eenth`\, n.
   1. The quotient of a unit divided by eighteen; one of
      eighteen equal parts or divisions.
      [1913 Webster]

   2. The eighth after the tenth.
      [1913 Webster]
    

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