Definition

1. Noun:
   • The 150th anniversary of an event: A sesquicentennial marks the passage of 150 years since a significant occurrence.
   • The celebration of a 150th anniversary: A sesquicentennial is also the event or series of events held to commemorate this milestone.

Usage

• The word "sesquicentennial" is a formal term used primarily in historical, institutional, and governmental contexts. It is not commonly used in everyday conversation.
• It functions as a countable noun. You can have sesquicentennial or celebrate sesquicentennial of an institution.

Examples

• As the anniversary:

  • The university is preparing for its sesquicentennial next year.
  • The sesquicentennial of the town's founding will be in 2025.

• As the celebration:

  • The city's sesquicentennial featured a parade and a historical exhibition.
  • They published a special book for the library's sesquicentennial.

Advanced Usage

• Sesquicentennial can be used attributively as a noun modifier (functioning like an adjective) before another noun.
  • The sesquicentennial committee planned the events for months.
  • We attended the sesquicentennial concert in the park.

Variants and Related Words

• Sesquicentenary: This is a less common synonym with the same meaning as "sesquicentennial."
• Centennial (noun): The 100th anniversary or its celebration.
• Bicentennial (noun): The 200th anniversary or its celebration.

Synonyms

• 150th anniversary: A more common, descriptive phrase for the same milestone.

Antonyms

• There are no direct antonyms, but terms for other anniversaries serve as contrasts (e.g., centennial for 100 years, bicentennial for 200 years).

Word Origin and Notes

• Etymology: The word is formed from the Latin prefix meaning "one and a half" (from "half" + "and") and (from Latin "hundred" + "year"). It literally means "one and a half hundred years."
• Frequency: This is a low-frequency word, typically encountered in formal writing, news reports about major anniversaries, or academic historical texts.

Noun

1. the 150th anniversary (or the celebration of it)