English Reference
Idiom idiom

red letter day


A particularly significant day; a day of personal or sectarian celebration.

Meaning adapted from Wiktionary, available under CC BY-SA 4.0.


SIMPLE

Today is a red letter day for our family.

CONTEXTUAL

Graduating from university after years of hard work was truly a red letter day for her.

COMPLEX

The signing of the peace treaty marked a red letter day in the nation's history, signaling the end of decades of conflict.


The expression alludes to a practice dating to classical antiquity, wherein important dates were marked in red ink on calendars. It remains a surviving trace of the ecclesiastical and civil custom of distinguishing festivals and saints' days from the black-inked mundane.


Related idioms8entries
  1. 01

    a cold day in July

    The time of occurrence of an event that will never happen.

  2. 02

    a day late and a dollar short

    Too late and too feeble to achieve the desired effect.

  3. 03

    a year and a day

    A long time.

  4. 04

    all one's born days

    One's whole life.

  5. 05

    as the day is long

    Unceasingly; very; thoroughly; to a very high degree.

  6. 06

    bad hair day

    A day when things seem to be unmanageable or go wrong.

  7. 07

    bad old days

    The past, seen as a time when things were worse.

  8. 08

    banyan day

    In British naval tradition, a day of the week when galley kitchens served no meat on board ship.

Last updated August 10, 2026