The number eighteen.
eighteen definition by Webster's New World
Origin: Middle English eightetene ; from Old English eahtatiene: see eight and amp; teen
eighteen definition by American Heritage Dictionary
- The cardinal number equal to 17 + 1.
- The 18th in a set or sequence.
Origin: Middle English eightetene, from Old English eahtatēne; see oktō(u) in Indo-European roots.
- eight·eenˈ adjective & pron.