What does eighteenth mean?
"Eighteenth" is the ordinal form of the number eighteen, indicating position or sequence rather than quantity: it denotes whatever comes immediately after the seventeenth, whether in a list of centuries, a row of houses, a line of amendments, or a round of golf. As an adjective it modifies a noun directly — "the eighteenth century," "his eighteenth year" — while as a noun it stands alone for the item itself in that position, as in "she finished eighteenth." It is written out in formal prose and abbreviated as "18th" elsewhere, and it is normally preceded by "the." Because ordinals are essential for dates, anniversaries, rankings, and legal instruments, "eighteenth" is a routine but indispensable word; its most frequent companions are "century," "birthday," and "hole," reflecting its common use in historical discussion and everyday milestones.
Coming next after the seventeenth in order; constituting number eighteen in a series.
"The house was built in the eighteenth century."
Almost always takes the definite article when referring to a specific position.
The person or thing in the eighteenth position in a series.
"He finished eighteenth in the marathon."
In sports results, ordinals like this often function adverbially without an article.
Golfers call their final hole "the eighteenth" so universally that it has become shorthand for finishing anything at all.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of eighteenth
"Eighteenth" is formed within Old and Middle English from "eighteen" plus the ordinal suffix "-eth" (from Old English "-þa"), which marks ordinal numbers much as "-th" does today. Its root traces back through Middle English "ehteotene" to Old English "eahtatiene," combining "eahta" (eight) with "-tiene" (ten), ultimately from Proto-Germanic origins shared by German "achtzehn" and Dutch "achttien." Cognates across Germanic languages show the same transparent construction, making this a native English formation rather than a borrowing from Latin or French.
How eighteenth is actually used
Ordinals like "eighteenth" are typically used with the definite article ("the eighteenth of June") and are written as superscript numerals (18th) in informal contexts. In dates, British English often uses "the eighteenth of June," while American English prefers "June eighteenth." The word carries no strong connotation and appears equally in formal and casual register.
Easily confused with eighteenth
"Eightieth" means 80th in a sequence, while "eighteenth" means 18th.