The color red has multiple, often contradictory significations: blood and sacrifice, anger, high rank and luxury, celebration.  It appears on the ceremonial vestments of cardinals in the Roman Catholic Church and, as a hue long associated with socialist revolution, on the flag of the People’s Republic of China.  Louis XIV of France liked modishly red shoes, as does the heroine of the contemporary German film Barbara.  Worn even while she bikes, red high heels bring a touch of chic to the otherwise drab East Germany of the 1980s:

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You want to be given red roses on Valentine’s Day, find in your mailbox a red envelope from Netflix, or bring up on your computer screen the red icon of You Tube, but you do not want to see red ink on your balance sheet or be shown a red card on the soccer pitch.  The only thing all these significations would seem to have in common is vibrancy: red is a color meant to be noticed.

A “rubric,” from Latin ruber (“red”), originally something noteworthy printed in that color, say instructions for conducting a church service or the heading for a book chapter, now means more generally “instructions,” “guidelines,” a “set of rules”; teachers are supposed to follow “grading rubrics,” which are invariably disseminated in the staid black typeface of reports from the local Department of Education.  This semantic evolution is like that seen with “etiquette,” namely a shift from the literal to the conceptual, from words on a physical document to what those words are concerned with. 

As for the related term “red-letter,” its meanings have evolved too.  In the Middle Ages, red letters on a calendar marked out church festivals or important saints’ days,

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whereas in current usage “red-letter” refers to any day which anyone deems highly successful or otherwise significant.  We have democratized the term.  One would expect that in the calendar app of an iPhone, red would be used to single out dates to which a memo’s been added—e.g.,”dentist appointment 10:30,” “report due 😥 ,” “buy milk on way home!!!”—but no, those dates just get a little dot underneath them.  The only date colored red is . . . today.  That fact seems to say something about the cyberworld, where what really matters is not plans for next week and certainly not the history of yesterday, but today, this very moment, right now.