I. (ˈ)ā(t)|tēn sometimes (ˈ)ād.|ēn adjective
Etymology: Middle English eightetene, eightene, from Old English eahtatīene, eahtatȳne, eahtatēne (akin to Old High German ahtozehan eighteen, Old Norse āttjān, ātjān ), from eahta eight + -tīene, -tȳne, -tēne (from tīen, tȳn, tēn ten) — more at eight , ten
: being one more than 17 in number
eighteen years
— see number table; used prepositively to designate certain years of the 19th century
the eighteen -eighties
the early eighteen -hundreds
II. pronoun, plural in construction
Etymology: Middle English eightetene, eightene, from Old English eahtatīene, eahtatȳne, eahtatēne, from eahtatīene, eahtatȳne, eahtatēne, adjective
: 18 countable persons or things not specified but under consideration and being enumerated
eighteen are here
III. noun
( -s )
1. : 10 and eight : twice nine : nine times two : three times six
2.
a. : 18 units or objects
a total of eighteen
b. : a group or set of 18
3. : the numerable quantity symbolized by the arabic numerals 18
4. : the 18th in a set or series ; especially : an article of clothing of the 18th size
wears an eighteen
5. : eighteenmo — usually used in plural
a book printed in eighteens
6. : something having as an essential feature 18 units or members