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Synonyms

red-letter

American  
[red-let-er] / ˈrɛdˈlɛt ər /

adjective

  1. marked by red letters, as festival days in the church calendar.

  2. memorable; especially important or happy.

    a red-letter day in his life.

  3. (of a Bible) having the quoted words of Jesus appear in red type.

    a red-letter edition;

    the red-letter New Testament presented at her baptism.


Etymology

Origin of red-letter

First recorded in 1660–70

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

This makes July 10, 2026, the red-letter day because taxpayers usually have three years after filing a return to make a claim disputing a penalty, according to Collins.

From MarketWatch • May 27, 2026

SpaceX’s big news, along with Anthropic’s showing potential to turn a profit far sooner than expected and OpenAI’s prepping for its public debut, made yesterday AI’s red-letter day.

From The Wall Street Journal • May 21, 2026

His 24 points - his highest tally in a Test match - included two tries, but his kicking, vision and communicative skills laid the foundation for Ireland's red-letter day.

From BBC • Sep. 10, 2023

Could Feb. 15 be a red-letter day for Nikki Haley?

From Washington Times • Feb. 7, 2023

Remember yesterday’s date, since it was a red-letter day for me.

From "The Diary of a Young Girl" by Anne Frank

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