Question

in_the_loop_599 an important day; a day to remember The expression originates from the practice of marking holy days in red on some calendars.

Accepted Answer

RED-LETTER DAY Tomorrow is going to be a red-letter day for our school. The president is coming to speak to the students and faculty.Mike was made a vice president of the company yesterday. It certainly was a red-letter day for him.

Id	in_the_loop_599
Idiom	RED-LETTER DAY
Definition	an important day; a day to remember
Examples	Tomorrow is going to be a red-letter day for our school. The president is coming to speak to the students and faculty. Mike was made a vice president of the company yesterday. It certainly was a red-letter day for him.
Extra Info	The expression originates from the practice of marking holy days in red on some calendars.

Day Red Letter President Loop Important Remember Tomorrow School