Red Letter Day

A red letter day (sometimes hyphenated as red-letter day or called scarlet day in academia) is any day of special significance or opportunity. Its roots are in classical antiquity; for instance, important days are indicated in red in a calendar dating from the Roman Republic (509–27 BC). In medieval manuscripts, initial capitals and highlighted words (known as rubrics) were written in red ink. The practice was continued after the invention of the printing press, including in Catholic liturgical books. Many calendars still indicate special dates and holidays in red instead of black. The practice did not originate, as it often assumed, from Medieval church calendars or a requirement that important holy days be marked in red from First Council of Nicaea in 325 AD, as has widely been claimed.

On red letter days, judges of the English High Court (Queen's Bench Division) wear, at sittings of the Court of Law, their scarlet robes (see court dress). Also in the United Kingdom, other civil dates have been added to the original religious dates. These include anniversaries of the Monarch's birthday, official birthday, accession and coronation. In the universities of the UK, scarlet days are when doctors may wear their scarlet 'festal' or full dress gowns instead of their undress ('black') gown.

In Norway, Sweden, Denmark and South Korea and some Latin American countries, a public holiday is sometimes referred to as "red day" (rød dag, röd dag, 빨간 날), as it is printed in red in calendars.

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