Symbol of X – Origin and Meaning

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The most powerful letter in the alphabet, the symbol of X has been used in so many fields, from algebra to science, astronomy and spirituality. It’s commonly used to represent the unknown, but its meanings may vary depending on the context. Here’s what to know about the significance of the X symbol, along with its origin and history.

Symbolism of x

Meaning of the Symbol of X

The X symbol has diverse meanings, representing the unknown, secrecy, danger, and the end. It can have mystical significance, as well as scientific, or linguistic importance. Here are some of the meanings of the symbol, along with its usage in various contexts:

Symbol of the Unknown

In general, the X symbol is used to denote something mysterious or unknown, meant to be solved. In algebra, we’re often asked to solve x as a variable or a value that’s not yet known. In the English language, it’s commonly used to describe something vague, such as Brand X, or to signify a mysterious person, such as Mr. X. In some contexts, it’s also used for confidential documents, thing, person, or place.

Symbol of the Known

Sometimes, the X symbol is used for labeling specific locations or destinations on maps and meeting places, leading to the expression x marks the spot. In fiction, it’s commonly found on treasure maps, showing where the hidden treasure is buried. It can also be used to mark the place where skydivers should land, or where actors should be on a stage.

In modern uses, X is regarded as a universal signature for those who can’t read or write, indicating their identity, or agreement on a contract or document. Sometimes, it also marks the portion where a document should be dated or signed. Nowadays, we use it to indicate a choice, be it on an exam or ballot, though the same symbol is used for marking the scene of a crime in photographs, or plans.

Danger and Death

Some associate the X symbol with the overlapping femurs or the skull-and-crossbones that signify danger and death. While the crossbones first became associated with pirates, on the Jolly Roger insignia, they became a generalized hazard warning by the end of the 19th century.

Later, both skull-and-crossbones and X symbol on an orange background became the standard for labeling harmful and toxic substances throughout Europe. It’s likely one of the reasons why the X symbol gained a macabre relationship with death.

Error and Rejection

Most of the time, the X symbol is used for the concept of error and rejection. For instance, it’s used to indicate wrong answer, especially on an exam, as well as a cancellation that requires a do-over.

The End of Something

In some context, the symbol of X signifies an entity whose existence is over, past, and gone. In technical use, the letter X is often a shorthand version of a longer prefix ex, commonly used to describe former relationships, such as ex-husband, ex-friend, ex-band, or ex-CEO. In informal language, some use the letter X when referring to their ex-spouse or girlfriend.

A Modern Symbol for Kiss

In 1763, the X symbol for kiss was mentioned in the Oxford English Dictionary and used by Winston Churchill in 1894 when he signed a letter. Some theory suggests that the letter itself resembles two people kissing with the symbols > and < meeting like a kiss, creating the symbol X. Today, it’s widely used at the end of emails and text messages to signify a kiss.

History of the X Symbol

Before gaining its mystic significance, X was a letter in the early alphabet. Later, it was used to represent the unknown and a variety of concepts in mathematics and science.

In Alphabetic Symbolism

The first alphabet appeared when pictograms evolved into symbols that represented individual sounds. X is derived from the Phoenician letter samekh, which represented the /s/ consonant sound. After 200 years, from 1000 to 800 BCE, the Greeks borrowed the samekh and named it chi or khi (χ)—the twenty-second letter of the Greek alphabet from which X developed.

In Roman Numerals

The Romans later adopted the Chi symbol to denote the letter x in their Latin alphabet. The X symbol also appears in Roman numerals, a system of letters used for writing numbers. Each letter in the system stands for a number, and X represents 10. When a horizontal line is drawn above X, it means 10,000.

In Mathematics

In algebra, the X symbol is now used to represent an unknown variable, value, or quantity. In 1637, René Descartes used x, y, z for unknown variables to correspond to a, b, c used to denote known quantities. Just take note that a variable doesn’t have to be indicated by the letter x, as it could be any other letter or symbol. So, its use for representing the unknown might have a deeper and earlier origin.

Some speculate that the use of the x symbol in mathematical equations stemmed from the Arabic word shay-un that means something or undetermined thing. In ancient text Al-Jabr, a manuscript that established the rules of algebra, mathematical variables were referred to as undetermined things. It appears throughout the text to represent the part of the equation that’s not yet identified.

When the manuscript was translated by Spanish scholars, the Arabic word shay-un couldn’t be translated because Spanish has no sh sound. So, they used the closest sound, which is the Greek ch sound represented by the letter chi (χ). Eventually, these texts were translated into Latin, where the translators simply replaced the Greek chi (χ) with the Latin X.

In Science and Other Fields

x-ray hand

After the use of the symbol in algebra, the x symbol was eventually used to represent the unknown in other circumstances. When physicist Wilhelm Röntgen discovered a new form of radiation in the 1890s, he called them X-rays because he didn’t fully understand them. In genetics, the X chromosome was named for its unique properties by early researchers.

In aerospace, the x symbol stands for experimental or special research. In fact, each aircraft is recognized by a letter that designates its purpose. X-planes have accomplished several aviation firsts, from innovations to breaking altitude and speed barriers. Also, astronomers have long used X as the name of a hypothetical planet, a comet of unknown orbit, and so on.

The Symbol of X in Different Cultures

Throughout history, the X symbol has gained various interpretations based on the context within which it’s viewed.

In Christianity

In the Greek language, the letter chi (χ) is the first letter in the word Christ (Χριστός) pronounced khristós, meaning the Anointed One. It’s thought that Constantine had seen the Greek letter in a vision, which led him to adopt the Christian faith. While some associate the X symbol with the cross, scholars say that the symbol is more identical to the pagan symbol for the sun.

Today, the X symbol is often used as a symbol for the name Christ. As a graphical device or Christogram, it replaces the word Christ in Christmas, which therefore becomes Xmas. The other popular example is the Chi-Rho or XP, the first two letters of Christ in Greek superimposed over one another. In 1021 CE, the word Christmas was even abbreviated as XPmas by an Anglo-Saxon scribe to save some space in writing.

Some people are fond of symbols to represent their faith. However, the X symbol itself predates Christianity, as it was once the symbol of luck in ancient Greece. Nowadays, it remains a debate whether to use the X as a symbol of Christ in Xmas, considering the many negative meanings of X such as unknown and error, but some argue that the controversy is only a misunderstanding of language and history.

In African Culture

For many African-Americans, the histories of their surnames were influenced by slavery in the past. In fact, the X symbol is a marker of absence for an unknown African surname. During slavery, they were assigned names by their owners, and some didn’t have a surname.

The most influential figure is Malcom X, an African American leader and supporter of Black nationalism, who took the surname X in 1952. He said that it symbolized the unknown African name of his ancestors. It might seem like a bitter reminder of slavery, but it can also be a declaration of his African roots.

The Symbol of X in Modern Times

The sense of mystery in the X symbol has led to its wide use in naming, from Malcom X to the Generation X, and sci-fi television series X-Files and X-Men.

As a Label of Demographic Group

The symbolism of X was applied to Generation X, the generation born between 1964 and 1981, likely because they were young people whose future was uncertain.

The term Generation X was first coined by Jane Deverson in a 1964 publication, and popularized by Canadian journalist Douglas Coupland in 1991’s novel, Generation X: Tales for an Accelerated Culture. It’s said that the X is used to describe a group of people who didn’t want to concern themselves with societal status, pressure and money.

However, some speculate that the X was given to the name Gen X because it’s the 10th generation since 1776—and in Roman numerals X stands for 10. It’s also the generation that marks the end of the Baby Boom generation.

In Pop Culture

The sci-fi television series X-Files had a cult following in the 1990s, as it revolves around paranormal investigations, existence of extraterrestrial life, conspiracy theories, and paranoia about the US government.

In the Marvel comics and movie X-Men, the superheroes had an x-gene, which resulted to extra powers. The 1992 American film Malcolm X narrates the life of the African-American activist who lost his original name in slavery.

In Email and Social Media

Nowadays, the X symbol is widely used at the end of letters to indicate a kiss. Sometimes, the uppercase (X) signifies a big kiss, though it shouldn’t always be regarded as a sign of romantic gesture. Some people simply include it in messages to add a warm tone into it, making it common among friends.

In Brief

Each of the letters in the alphabet has a history, but X is the most potent and mysterious. Since its inception, it has been used to represent the unknown, and has more social and technical uses than any other letter in the English alphabet. Nowadays, we use the symbol in mathematics, to mark places on a map, to indicate our choice of candidates on a ballot, to indicate an error, and many more.

Nina Jay

Nina Jay

Nina Jay has worked as a writer and editor for over 15 years. She holds a Masters degree in Linguistics and Education, and has also studied Political Science, Ancient History and Literature. She has a wide range of interests ranging from ancient cultures and mythology to Harry Potter and gardening. She works as the chief editor of Symbol Sage but also takes the time to write on topics that interest her.

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