Knock three times.
Dear Word Detective: Well, we all know what the question “Are you decent?” means, but how and when did it come to be that very specific question referring to one’s state of (un)dress? — Your Humble Reader, Nick.
Mmm, humble. That’s the spirit. “Are you decent?” is an interesting idiom in part because it doesn’t seem like an idiom, which is a fixed phrase that has more meaning (or a different meaning) than the literal sum of its words (e.g., “piece of cake” meaning “something easily done”). “Are you decent?” seems to be the most basic of simple, factual questions, on a par with “Are you married?” or “Is that your dog driving my car?” But what it really means, as an idiom, is “Are the parts of your body considered not fit for public viewing according to societal norms in this particular historical period sufficiently obscured so as not to cause either of us embarrassment and/or lasting mortification?”
“Decent,” of course, is one of more popular English adjectives (certainly more popular than “crepuscular,” which means “dim, indistinct, resembling twilight” and is one of my favorite words). English adopted “decent” in the 16th century from the French word “decent,” which was based on the Latin “decentem” (“fitting, appropriate, proper”), which was a form of “decere,” meaning “to be proper or seemly.”
The initial meaning of “decent” in English concerned the tenets of social respectability at the time; what was “decent” was what was appropriate to one’s rank or station and socially fitting given the facts of a situation (“The funerall of the Bish[op] of Hereford …was a decent solemnity..,” circa 1684). We still use this “appropriate” or “seemly” sense when we speak of waiting a “decent” time before criticizing someone who has died or spending a “decent” amount of time on social obligations (“After a decent Time spent in the Father’s House, the Bridegroom went to prepare his Seat for her Reception,” 1710).
By the 17th century, “decent” had broadened a bit to also mean “in good taste,” “sufficient” (“decent salary”) and even “handsome or attractive,” especially as applied to dwellings (“He had Five or Six Apartments in his House …Two of them were very large and decent,” Daniel Defoe, 1725).
Bubbling along under the “socially appropriate” usage of “decent” all this time had, however, been a different use of “decent” in a “personal morality” sense, specifically to mean, as the Oxford English Dictionary defines it, “In accordance with or satisfying the general standard of propriety or good taste, in conduct, speech, or action; especially conformable to or satisfying the recognized standard of modesty or delicacy; free from obscenity.” Yes, folks, we’re entering the zone of foul-mouthed nekkid people here. This is the sense of “decent” invoked by centuries of fervid campaigns against obscenity, pornography and other sorts of “indecency,” from which a pass can be earned only by clinical detachment, such as that of an anthropologist encountering people safely far away (“The Wa-Caga cannot be accused of indecency, for they make no effort to be decent, but walk about as Nature made them,” H. H. Johnston, Kilimanjaro Expedition, 1886). Today cable TV and the internet are, of course, full of people wandering around “as Nature made them” (albeit often with unnatural enhancement), so “decency” in this sense has lost a bit of its oomph in many quarters, though it still gets votes in the boonies.
All of which brings us back to “Are you decent?” as a pause-at-the-door formality. Interestingly, the phrase seems to have originated as a jocular usage among theater performers, as explained in a 1949 book by Ruth Harvey called “Curtain Time”: “Sometimes, if she knew one of the actors or actresses, she would knock at a door and call ‘Are you decent?’ (That old theatrical phrase startled people who didn’t belong to the theatre, but it simply meant ‘Are you dressed?’).” Given that actors would be well aware that government agencies as well as self-appointed Decency Cops were constantly monitoring stage productions for “indecency” during most of the 20th century, it’s likely that the “decent” in the phrase was a joking reference to the standards of propriety applied to performers on stage, and not just a random synonym for “dressed.”