Red-letter Day Definition & Meaning - Merriam-Webster

✨📕 The NEW Collegiate Dictionary, 12th Edition Over 5,000 words added — Learn More! ✨📕 The NEW Collegiate Dictionary — Learn More! Est. 1828 Dictionary

• Definition
• Definition
• Entries Near

• • Cite this EntryCitation
  • Share
  • More from M-W
  Show more
• Show more
  • Citation
  • Share
  • More from M-W

• Save Word
  • To save this word, you'll need to log in. Log In

red-letter day

noun

informal : a very happy and important day

Browse Nearby Words

red-letter red-letter day red-light See all Nearby Words

Cite this Entry

Style MLA Chicago APA Merriam-Webster

“Red-letter day.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/red-letter%20day. Accessed 12 Dec. 2025.

Copy Citation

Share

More from Merriam-Webster on red-letter day

Nglish: Translation of red-letter day for Spanish Speakers

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Merriam-Webster unabridged

More from Merriam-Webster

Can you solve 4 words at once?

Play Play

Can you solve 4 words at once?

Play Play

Word of the Day

waggish

See Definitions and Examples »

Get Word of the Day daily email!

Popular in Grammar & Usage

See More

'Affect' vs. 'Effect'

'Buck Naked' or 'Butt Naked'?

31 Useful Rhetorical Devices

The Difference Between 'i.e.' and 'e.g.'

Why is '-ed' sometimes pronounced at the end of a word?

See More

Popular in Wordplay

See More

More Words with Remarkable Origins

Top 10 Sophisticated Insults

17 Words for Dog Breeds

How 'Namaste' Entered The English Language

'Za' and 9 Other Words to Help You Win at SCRABBLE

See More

Popular

See More

'Affect' vs. 'Effect'

More Words with Remarkable Origins

Top 10 Sophisticated Insults

See More

Games & Quizzes

See All Quordle Can you solve 4 words at once? Play Blossom Pick the best words! Play The Missing Letter A daily crossword with a twist Play Name That Animal: Volume 3 Who’s who of the zoo crew Take the quiz See All