Definitions

1. adjective

being or coming next after seventeenth in a series or sequence

“The eighteenth century saw significant advancements in science and technology.”

2. noun

the position or rank of eighteenth in a series or sequence

“The eighteenth seat in the auditorium had a good view of the stage.”

3. adverb

used for emphasis or to indicate a specific time or position

“The team was crowned the eighteenth national champion in the country’s history.”