Of American-English origin, the phrase five o’clock shadow, also 5 o’clock shadow, denotes the beard growth which becomes visible in the late afternoon on the face of a man who has shaved earlier in the day.
—Cf. also ‘beer o’clock’: 5 p.m. as the end of the working day.
The phrase first occurred—as 5 o’clock shadow—in 1937 as the catchline of an advertising campaign for Gem Micromatic Razor and Blades. For example, the following advertisement was published in Life (New York City, New York) of Monday 6th September 1937:
DON’T LET “5 O’clock Shadow” START A WHISPERING CAMPAIGN
Let down a little in your personal appearance and it’s just human nature for others to surmise that things aren’t so good with you!
“5 O’clock Shadow”—that unsightly beard growth which appears prematurely at about 5 P.M., looks bad. There’s no denying that! It’s caused directly by using inefficient shaving instruments which merely “top” the beard. Note this well: A Gem Blade in a Gem Razor guarantees shadowless shaves which last to the end of the longest day!
For the Gem Micromatic Razor is scientifically right. Its built-in, face-fitting bevel hugs every facial contour; compels the long, smooth, gliding stroke of the master barber; shaves at the one correct angle, clean and close at the dermal line. All one piece, Gem is the world’s easiest razor to use. Twist, it opens; twist, it closes.
The Gem Micromatic Blade is made of 50% thicker surgical steel and so can be given a deeper beveled edge. This edge is stropped 4840 separate times to increase keenness. A keenness that lasts. You get cleaner shaves and far more of them to each blade.
Stay clean with Gem! One dollar buys a Gem Razor with 5 blades, handsomely cased, at all dealers. Or send coupon below and 25¢ for convincing “proof” offer.
In his column, Hard Lines and Old Times, published in the Rutland Daily Herald (Rutland, Vermont) of Thursday 18th November 1937, the Vermont author Walter Hard (1882-1966) reacted negatively to the advertising campaign’s catchline:
It is doubtless true that many an advertising campaign has been successful in selling something in a big way just because it had a clever catch phrase. In the patent medicine line and the cosmetic world there is little question that this cleverness of phrase is much more important than the quality of the goods.
So often, however, speaking now of our own comfort and not of salesmanship, the putting of something we knew all along was a bit unpleasant into a smart sentence or giving it a name, makes it loom as one of life’s major impediments to happiness. […]
Now comes a new one to pester the man with dark whiskers ever lurking. It comes with a new shaving device advertising build-up of course. “Five o’clock shadow” is the new tragic thing which hangs over the man who does not have just this particular whisker mower in his boudoir kit. Having performed a fairly good barbering job before the morning mirror we have usually allowed ourself to feel shaven for the whole day. Now, as sure as fate we’re going either to get self conscious along about 5 o’clock (as the shadows fall) or else we’ll emerge from the shaving routine of the morning looking as though we’d been in mortal combat with a sausage grinder.
Moral: Don’t be feazed by a phrase!
The earliest occurrence that I have found of five o’clock shadow used as an independent phrase (i.e., without explicit allusion to the advertising campaign) is from the caption to the following photograph, published in The Daily Oklahoman (Oklahoma City, Oklahoma) of Saturday 20th November 1937:
That Five o’Clock Shadow’s Here Again
WE’RE RUFF, WE’RE TUFF—Come out from behind those beards, men—we know you! You’re Ruf-Nek pledges down at the University of Oklahoma, and according to that quaint old campus custom, you won’t get to shave until initiation. There being a good many Ruf-Nek pledges, all of whom seem considerably good at raising roughage this year, the Norman campus looks scraggly but manly this time of year. Here are some of the college boys in a campus shop—not a scene from Old Joe’s Barroom.