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The X factor -

With his rebranding of Twitter, Elon Musk ditched the company's iconic blue bird logo in favor of a far more ominous X. "Twitter was acquired by X Corp both to ensure freedom of speech and as an accelerant for X, the everything app," explained the billionaire tech magnate.

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A fascination with X -

Elon Musk has long held a fascination with the letter X. Just look at SpaceX and the Model X, one of electric car company Tesla's earliest models, and his artificial-intelligence app xAI. Taking things further, even the son he shares with musician Grimes is nicknamed X!

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Ex-Twitter -

Musk formally changed Twitter's legal name to X Corp in April 2023. But what is it about this least-used letter of the alphabet that makes it so compelling? For that answer, we have to delve deep into the past.

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Origins of the letter X -

The letter X emerged as part of the Phoenician alphabet, around 1050 BCE. Known as the samekh and shaped to resemble a fish, the letter was later adopted and adapted by other cultures.

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Greek alphabet -

The Phoenician X gave rise to the Greek xi, the 14th letter in the Greek alphabet and, confusingly, distinct from the letter X, the 22nd letter in the alphabet, which is known as chi.

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Roman alphabet -

It was the Romans who took the Greek chi and incorporated the letter into their own alphabet. From this we get the letter X, the 24th letter of the Latin alphabet.

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X = 10 -

After conceiving their alphabet, the Romans designed their numerical system using combinations of Latin letters. The number 10 was identified by an X.

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X as a symbol of spirituality -

The place where Christ was crucified is sometimes marked by an X. The letter can also refer to Christ himself.

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The meaning of Xmas -

Xmas is informal shorthand for Christmas. While the letter X has come through church history to be a symbol for the name of Christ, the "mas" in Xmas comes from the Old English word for mass—mæsse—as in a church service.

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X as a symbol of evil -

The letter X can represent evil and death. The Jolly Roger, otherwise known as the skull and crossbones, is a symbol consisting of a human skull and two long bones crossed together under or behind the skull. It's often associated with piracy.

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Poisonous substance -

The skull and crossbones is also the classic symbol for a toxic chemical. It is usually placed on an orange background.

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X as a symbol of daring and danger -

The US military's propensity to slap an X on its secret high-flying aircraft, such as the North American X-15 (pictured), demonstrates the letter's use as a symbol of nerve and derring-do. In fact, in aerospace the X symbol stands for experimental or special research.

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X-sports -

X-sports, or extreme sports, denote dangerous, high-risk leisure pursuits such as free solo climbing and wingsuit flying.

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X in mathematics and science -

In mathematics, X is the symbol for multiplication and used in times tables.

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The x-variable -

In algebra, the x-variable is the most common variable used for unknowns.

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X as a symbol of the unknown -

The letter X is employed to denote something that is mysterious or unknown and meant to be discovered or solved. The cult TV series 'The X-Files' kept Mulder and Scully forever trying to find out if the truth was out there.

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The X-ray -

When physicist Wilhelm Röntgen discovered a new form of radiation in the 1890s, he called them X-rays. He based his description on the use of the X in algebra, and its association with the unknown. He simply didn't know what else to call it!

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Malcolm X -

Malcolm X, a vocal advocate of black empowerment, explained that the "X" he used stood for his unknown African name.

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X as a symbol of the known -

Paradoxically, the letter X is also used to represent the known, to mark a specific location on a map for example. Think "X marks the spot."

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Pinpointing a specific spot -

An X can also denote an exact place to stand or be seated—an actor's position on stage for example, or for the placement of furniture.

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X as the affirmative -

An X is the traditional symbol used to mark an electoral ballot paper. It's also employed to answer multiple choice questionnaires.

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X to denote error and rejection -

The letter X, especially when written using red ink, is used to indicate an error or a wrong answer, very often across an exam paper or something similar.

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The "ex" in relationships -

Symbolically, the letter X is often a shorthand version of a longer prefix ex, used to describe a breakup or a former relationship. An ex-husband perhaps, or an ex-colleague and suchlike.

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The X as a kiss -

On a happier note, XOXO means "hugs and kisses." The X represents a kiss, while the O represents a hug.

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The X in sex determination -

The X chromosome is one of the two sex chromosomes that are involved in sex determination. Females have two X chromosomes in their cells, while males have one X and one Y.

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X-rated cinema -

Introduced in 1968, an "X" rating designated films meant strictly for adults.

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Generation X -

Generation X (often shortened to Gen X) is the demographic cohort born between 1964 and 1981 who didn't want to concern themselves with societal status, peer pressure, or money.

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The power of the X-gene -

In the 'X-Men' franchise, the superheroes are named after founder Charles Xavier but are also known to have an X-gene, which gives them incredible powers.

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The X in a name -

In numerology, if the first letter of your first name starts with X, for example Xavier or Xana, you are balanced, attractive, and lovable in personality. Its numerical value of X is 6, thus people with X in their names tend also to be creative, tranquil, and helpful.

Sources: (CBS News) (Britannica) (The Guardian) (The Washington Post)

See also: The best cuisines in the world, ranked

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