eighteen
UK: eɪˈtiːn | US: eɪˈtiːn
n. the number equivalent to the sum of ten and eight; 18.
The word "eighteen" combines "eight," derived from Old English eahta (related to Proto-Germanic ahtōu), with the suffix "-teen," from Old English -tīene (a variant of tēn, meaning "ten"). This structure follows the Germanic pattern for forming teen numbers (13–19), where the unit digit precedes the suffix "-teen," originally meaning "ten more than." The logic reflects counting systems where numbers beyond twelve were expressed as additions to ten (e.g., "eight + ten").
She turned eighteen last month and is now eligible to vote.
The recipe requires eighteen ounces of flour.
There are eighteen students in the advanced class.
The train departs at eighteen minutes past the hour.
Chapter eighteen of the book reveals the final clue.