eighteenth

1 of 2

adjective

eigh·​teenth (ˈ)ā(t)¦tēn(t)th sometimes (ˈ)āt¦ē- 

1

: being number 18 in a countable series

the eighteenth day

see Table of Numbers

2

: being one of 18 equal parts into which something is divisible

an eighteenth share of the money

eighteenth

2 of 2

noun

"

plural eighteenths

-n(t)s, 

-n(t)ths

1

: number 18 in a countable series

the eighteenth of the month

2

: the quotient of a unit divided by 18 : one of 18 equal parts of something

one eighteenth of the total

Word History

Etymology

Adjective

Middle English eightetenthe, eightenthe, adjective & noun, alteration (influenced by eightetene, eightene) of eightetethe, eightethe, from Old English eahtatēotha, eahtēotha (akin to Old Norse āttjāndi, ātjāndi eighteenth), from eahtatīene, eahtatȳne, eahtatēne eighteen + -otha, -tha -th

Noun

Middle English eightetenthe, eightenthe

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Rhymes for eighteenth

• fifteenth
• fourteenth
• nineteenth
• sixteenth
• thirteenth
• umpteenth
• seventeenth