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How XO Came to Mean Kisses and Hugs

The religious and literary history of "XOXO."

Key points

  • XOXO has become a common way to sign off texts and emails
  • X started as the sign of the cross and gradually morphed through history into a kiss.
  • O's origins remain more mysterious but some theories suggest it came from games, arm circles or Ellis Island.
Source: Sanneberg/Shutterstock

As Valentine’s Day draws near, candy hearts emblazoned with XOXO, as in “hugs and kisses,” remind us that love is in the air. But why XO? Why not AB? Or XY? It turns out that XO, which has been becoming ever more popular as an affectionate sign off for texts and emails, had a fascinating journey on the way to becoming the modern call sign of “hugs and kisses.”

Kiss-Cross: Why "X" Marks the Kiss

According to the Oxford English Dictionary, the earliest evidence of the letter X symbolizing a kiss dates back to 1878, in the novel Seaforth by Florence Montgomery: “This letter...ends with the inevitable row of kisses,—sometimes expressed by × × × × ×, and sometimes by o o o o o o…” But since writing’s uptake of novel usage tends to follow that of everyday speech, it is likely that X was used in conversational contexts to stand in for “kisses” even earlier in the 19th century.

Prior to the 19th century, X appears instead to have been used to signal a blessing, as found in this letter dating back to 1763: “I am with many a xxxxxxx and many a Pater noster and Ave Maria.” We also find textual evidence during this period that X was also used to symbolize crosses, or the making of the sign of the cross (for example, as mentioned in the 1719 novel Robinson Crusoe). So, it seems before kisses came blessings.

It may not appear that blessing and kissing have that much in common. Yet, a deeper look into history gives us a hint about how the meaning of X might have morphed into its more common “kisses” meaning of today.

Sealed with an X

Earlier in history, X had become associated with the name of Christ, i.e., as in “Xmas” for Christmas. Because of this link to Christianity, the letter itself came to represent faith, fealty and devotion. This came in handy during the Middle Ages when most people were illiterate, so they would stamp an X, likely symbolizing a cross, into the wax used to seal important documents and letters in lieu of a signature.

Sometimes, after marking this X into the sealing wax, people would then put their lips to the mark to bless it or to swear an oath. As well, holy books were often kissed as they were opened and closed, as a show of faith and respect. Thus, this “sealing with a kiss” as a symbolic act might have helped establish a link between the X that was a cross and the X that became a kiss.

In the 19th century, literacy and letter writing became more common and letters were sometimes signed off with X. This practice originally was likely intended as a blessing but, owing to the overlap described above, gradually came to be associated with a kiss.

Source: Name_13/Pixabay
Noughts and Crosses?
Source: Name_13/Pixabay

Uh Oh: How "O" Came to Symbolize (Mostly) Hugs

The origin of X’s co-conspirator O is less clear. There is some evidence that the letter O could also be used to represent kisses, as in the previously mentioned quote from the 19th Century novel Seaforth, where the choice of X or O depended “on the taste of the young scribbler.”

More commonly and in modern usage, though, O is taken to represent a hug rather than a kiss. This meaning appears to be much more recent, with textual evidence suggesting an early to mid-twentieth century origin.

And why a hug? That is a good question and theories abound. Perhaps because its circular shape brings to mind being encircled by arms in an embrace, or perhaps due to its long-standing relationship with X in the game known as “Noughts and Crosses,” a.k.a, Tic-Tac-Toe. One final theory suggests that, because of X’s religious history, turn of the century Jewish immigrants to Ellis Island chose to sign using an O, so as not to use a Christian symbol.

Spread a little XO

No matter how the practice developed, modern texters and emailers have clearly embraced the friendly “give out a little love” vibe that XO projects. Using it with your boss or colleagues, though, might make for an awkward office party, so best to save your XOXO for those you really know and love.


Danesi, Marcel. 2013. The History of the Kiss: The Birth of Popular Culture. New York: Palgrave Macmillan

Epstein, Nadine. A whole lot of history behind ‘x’ and ‘o,’ kiss and hug. Washington Post. February 13, 2014.

Epstein, Nadine. The Secret History of X & O. Moment Magazine. March 4, 2014.

Oxford English Dictionary, s.v. “o (n.5),” July 2023, Accessed 1.14.23

Oxford English Dictionary, s.v. “X (n.),” September 2023, Accessed 1.14.23

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