eighteenth

[ ey-teenth ]

/ ˈeɪˈtinθ /

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

being one of 18 equal parts.

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

the eighteenth member of a series.

Origin of eighteenth

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

I can't rebuild my apartment on the fifth floor while you keep your apartment on the eighteenth floor just as it is.

Hell, No, Not So Low |Megan McArdle |October 16, 2012 |DAILY BEAST
William Blake, the eighteenth century poet, illustrator, engraver and mystic, worked from home but lived in his imagination.

William Blake's Heavenly Imagination |Chloe Malle |November 12, 2009 |DAILY BEAST
Then in the seventeenth and eighteenth centuries, as the cultivation of science became more general, royal academies were founded.

The Popular Science Monthly, October, 1900 |Various
The unfortunate natives of the eighteenth century allowed all kinds of havoc to be played with even their best-known names.

The Revival of Irish Literature |Charles Gavan Duffy

He had as little sympathy with liberty as Plato or as Bossuet, and less than the eighteenth century philosophers.

The Idea of Progress |J. B. Bury
It makes light of the sixteenth century, of the seventeenth, and of the eighteenth.

Ceres' Runaway |Alice Meynell
The nineteenth dynasty ended even more disastrously than the eighteenth.

Patriarchal Palestine |Archibald Henry Sayce

eighteenth

/ (ˈeɪˈtiːnθ) /

(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

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