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What's So Fascinating About the Letter X?

Why is "X" the most paradoxical and powerful letter—and symbol—of them all?

Source: mindsparx/123rf

What’s so mystifying about the letter “X?”

For starters, the swastika X—or cross—has come to symbolize the very essence of evil. And the letter, as signified by the skull and crossbones, portrays death by poison. Yet it also represents virtue and eternal life in being employed as an abbreviation for Christ in Xmas, and for Christianity generally. Such a curious dichotomy only hints at the many convoluted complexities of a letter seemingly “designed” to beguile us with contradictory connotations.

In this post, I’ll attempt the unusually challenging task of organizing the various meanings of this strangest, and most alluring, of letters. “X” may take up less space in the dictionary than any of its 23 compatriots but, in terms of its diverse uses, it’s a letter that defines, well, overcompensation. For it seems, waywardly, to want to sprawl out in every direction imaginable. As such, it rigorously resists all attempts to restrain it.

Nonetheless, I’ve sought here to somehow “rein it in,” to make this piece as comprehensible as possible, so as not to overwhelm the reader with the almost dizzying functions that, over the centuries, the letter has taken on.

Because it’s been employed in so many fields—from algebra, to genetics, to aerospace, to sex and spirituality—X’s abundant meanings have almost everything to do with the context that engages it. So in my efforts to categorize its disparate functions, I’ve struggled to find groupings that might accommodate its perversely “wandering,” or unstable, nature. Which is why some of my categories may seem arbitrary, and also why my last segment highlights its heterodoxy through the grabbag heading of “miscellaneous symbology.” For unquestionably, the broad array of meanings associated with “X” make all the other letters of the alphabet seem mundane—or puny—by comparison.

Even within contexts—say, the field of sports—X’s meaning can vary substantially. So, for example, a strike in baseball is not a good thing for a batter (and a strikeout even worse). But in bowling, a strike is a very good thing, for it means knocking down all 10 pins—or should I say "X pins" since, after all, X is the Roman numeral for 10. Moreover, an overall score of all X’s represents nothing short of bowling perfection (comparable to batting a 1,000!).

Finally, though, my proper function here isn’t to resolve the many incongruities surrounding this most captivating of letters but, more modestly, simply to enumerate them.

So, here goes:

1. Unknown vs. Known

The Unknown/Nebulous/Ambiguous/Mysterious/Vague/Variable/ Multitudinous ... and Top Secret (as it relates to a person, place, or thing)

So we have:

  • In mathematics, X as the symbol for multiplication.
  • In algebra, X as the variable—vs. a constant. We may be asked to "solve for X." t’s literally a puzzle—or unknown—meant to be deciphered. Jonathon Green, a lexicographer writing on X, wittily remarks that it “torments students of mathematics at all levels, from the common multiplication symbol in arithmetic to the more complicated X of algebraic equations."
  • In a Cartesian coordinate system, the x-axis as the horizontal of the x, y, and z.
  • In measurement, X as an added dimension, or by—as in a 3x5 card.
  • In advertising, as it depicts a generic version of the product being promoted—as in “Brand X”—conveniently unidentified and deprecated as inferior to the named brand.
  • In “secret societies,” X as employed to emphasize their strength, exclusivity, and a certain subversiveness, or duplicity, about them: expressed, for example, through crossed arms and legs, which can be code for “crossed” meanings—as in left meaning right, or things being inverted (e.g., black for white, yes for no, etc.).
  • In linguistics, X as what’s been called a “phonetic chameleon.” It’s used to replicate such sounds as “ks” (as in, “wax”), “gz” (as in, “exhaust”), “z” (as in, xenophobia), “k” (as in, “excite”), and “kzh” (as in, “luxury”). And the letter can also “hush up”—that is, be silent (as in, “Sioux Falls”). Wow, talk about diversity! Or confusion.

The Known/ Specific/Precise/Measurable/Identifiable ... or, Clearly Identifying Something, and Filling in a Blank (Where X Has an Unmistakable, Delimited Meaning)

So, in these instances, we have X as:

  • Marking ballot boxes to indicate a choice of candidate, or position on an issue.
  • Marking places on a map, to indicate the center, crossroad, or location of a mountain—as well as X marking the spot on a map where, presumably, a hidden treasure is buried.
  • Marking a defensive player in a football diagram.
  • Referring to “Generation X,” so named because at the time it was the 10th generation of Americans since 1776—though it’s employed specifically to designate the generation born following the peak of the post-WWII Baby Boom.
  • Marking the scene of a crime in a plan or photograph.
  • Signifying the crosshairs of a scope used to sight a firearm.
  • Indicating something's relative strength—as in the strength of an ale (Don Equis); XXX moonshine, with the number of Xs marking how many times a particular batch ran through the still; and XXXX is also a logo for a brand of Australian beer!

To sum up here, I’ll quote David Barringer, who states:

"The resonance of X as a signifier of mysterious precision [my italics to accentuate his "revealing" oxymoron] explains why it’s so common in commerce and branding. The Jaguar X-Type. The 2008 Mitsubishi Evolution X. The X2000, Sweden’s high-speed train. The X-Acto knife. Mac OS X. The X game for Nintendo’s Game Boy. Microsoft’s Xbox console. Vitamin Water XXX (with three antioxidants). The X is a California roller coaster (the seats swivel around). Product X is a protein powder for bodybuilders. The X-Vest adds weight for exercise."


2. Daring, Danger, Death—and Death Undefeated

This heading, not entirely distinct from others that follow, emphasizes some of the more “pointed” ways that X has been put to use. So we have:

  • The military’s propensity to attach an X to its mach-smashing aircraft, such as the X-1 or X-15. And, as in so many other applications (e.g., liquor, sex, and sports cars), there’s a certain macho quality that's become linked to the letter.
  • X-sports—short for Extreme sports—representing the most daredevil, risky (or reckless) of activities, seemingly calculated to tempt fate.
  • X as signifying the end of something—an entity whose existence is over, past, dead, and gone. Here, perhaps, we have X as the most “nihilistic” of letters. And curiously, cartoonists have traditionally employed it to display a character “out cold” or dead through drawing Xs over their eyes.
  • As already alluded to, as symbolizing fatality in the well-known skull and crossbones emblem.
  • In Kabbalistic philosophy, a branch of Jewish mysticism, as referring to both life and death.
  • X as a sign of the cross where Christ was crucified, or for Christ himself. But this symbol, or marker, can also be understood as a “crossing over” to another dimension: a transcendence, transformation, or transmigration.

3. Positive or Good; Negative, Bad, or Evil

Here, too, we have a plethora of possibilities. So my entries are hardly exhaustive and might be “assigned” to other categories as well. For a small sampling:

  • A rotated plus is the logo for the Red Cross (and, of course, X is all about “crossing”). In this context it signifies benevolence and humanity in helping those urgently in need.
  • In looking up prescribed, brand-name medications that begin with the letter “X,” I discovered a site listing over 50 of them—and that doesn’t even include those drugs (prescribed or OTC) whose names contain an X in the middle or end (like Lovenox, Zyprexa, or Sominex). A tiny sampling here would include: Xarelto, Xeljanz, Xenical, Xylocaine, and Xanax (which—“X-wise”—outdoes itself!).
  • Moving in the opposite direction, X has been used as a symbol of that which is negative, or a negation generally (i.e., null), such as crossing one’s fingers behind one’s back to void a promise being made;
  • X has long been recognized as an occult symbol for Satan, and the black art or witchcraft of satanism.
  • Witches cross their fingers to focus their energy and convey their possession of demonic powers; yet, on the other hand (no pun intended!), people cross their fingers to make a wish—doing it, for good (i.e., non-malignant) luck.
  • As a cross mark, X signifies an error or cancellation: so we have “X out,” “X off,” and “X over,” indicating the need for a do-over.
  • Being “cross” indicates petulant anger.
  • Being at “cross purposes” with another communicates conflict or contrariness.
  • Being “double-crossed” indicates being swindled, deceived, or betrayed.

4. Love, Sex, and Pornography (Maybe This Is What You've Been Waiting For?)

  • Adding an “O” for a hug (i.e., two individuals “encircling” one another) to an “X,” for a kiss (i.e., two lips “crossing over”), we get XOXO, or kisses and hugs—a basically affectionate symbol, free of any lurid sexual connotations; and also, xxx, typically understood as three little kisses;
  • X, as it relates not so much to a fond or sentimental attachment but to something far more lustful or passionate, gives us X-rated and the word sex itself. And not only does this usage address the earthier, more animalistic side of our nature, it can also slip into the realm of the naughty, illicit, or forbidden. Symbolizing explicit or graphic sexual content, we have extreme porn designated as XXX. And XXXX has been increasingly showing up to suggest really bold, intense, or outrageous displays of sexual derring-do.
  • Forex condoms, no longer manufactured, were probably the first XXXX-related product for men;

  • X has also been used to represent the anus, “the portal of transformation in ritual or key of David sodomy."

  • XXXX is now also used in written slang to signify the word “f**k”—as in, “Who gives a XXXX?!”

5. Miscellaneous Symbology

This highly condensed segment can only hint at everything that hasn’t yet been covered. And one irony here is that although X has an almost immeasurable diversity to it, it’s commonly used (as already described) for purposes of measurement. So:

  • In genetics, we have XX standing for the female pair of sex chromosomes (as distinguished from the male’s XY combination).
  • Racially considered, we get black Muslims’ appropriating, in place of their slave name, an X (i.e., unknown). Malcolm X is the best-known example of this.
  • X is implicated in taking a life/death oath—as in, “cross my heart and hope to die."
  • X signifies the sun god, a simple-rayed sun or star.
  • In clothing sizes, X means “extra,” as in “XS” for extra small, “XL” for extra-large, and so on.
  • X in aerospace stands for “experimental."
  • X is the diagnostic tool familiar to all of us as the X-ray.
  • Vitamin X refers to the rave or dance club drug, Ecstasy.
  • Camp X, aka Intrepid Park, refers to where experiments with mind control were done during WWII.
  • X-Files, in the cult hit TV series, represent mysterious, unsolved cases involving paranormal phenomena.
  • X-Factor, in the world of entertainment, signifies star quality—but now is more closely associated with ITV’s musical talent show.

That about completes my "pocket-sized" review of the intriguing letter X. And I hereby predict that—going forward—never will you view the consonant in the same way again!

© 2016 Leon F. Seltzer, Ph.D. All Rights Reserved.

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Barringer, D. (2007, Nov. 6). X for all or nothing.

Bishop, T. (2000, July 3). And you thought X was just another letter.

Green, J. X-rated: What is so special about the letter ‘X’ (2006, Nov. 6).

Meanings of the letter X, esoteric and otherwise.

What was the original name of the letter X, and how many sounds can it represent? (2011, April 26).

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