red-letter day(redirected from the red letter day)
A very important or significant day. My college graduation was a real red-letter day for my whole family.
Fig. an important or significant day. (From the practice of printing holidays in red on the calendar.) Today was a red-letter day in our history. It was a red-letter day for our club.
A special occasion, as in When Jack comes home from his tour of duty, that'll be a red-letter day. This term alludes to the practice of marking feast days and other holy days in red on church calendars, dating from the 1400s. [c. 1700]
a red-letter day
A red-letter day is a day when something very important or exciting happens. Back in 1986 Jim had his first picture published in BBC Wildlife Magazine. `That was a real red-letter day for me!' he confesses. Note: In the past, important feast days and saints' days were printed in red in some calendars.
n. an important day that might well be marked in red on the calendar. Today was a red-letter day in our history.