Maybe it would be better to say, “the & glyph was per se the 27th ‘character’ included with the alphabet.”
In Latin, the ampersand represents a cursive combination of the two letters E and T and is pronounced et, or and in English. Around the time when Old English was shedding its runic characters and adopting the Latin alphabet, the & ligature arrived as part of the orthographic package, and to this day continues to be used to represent the word and.
Why is called an ampersand?
The ampersand was included in schoolbooks as the 27th letter of the English alphabet until the mid 19th century. It was understood not as a vowel or consonant, but as a useful symbol, added to the hind end of the alphabet, and simply known as and. Today, when we recite the ABCs, we often say “X, Y, and Z.” Two centuries ago, children’s chants included and (&) as the last letter. To say “X, Y, Z, and and” was a bit awkward, so the Latin phrase per se – meaning “by or in itself “- was inserted. In recitations, it sounded like this: X, Y, Z, and per se and (&). Eventually, and-per-se-and slurred into ampersand, a mondegreen that we use today.
By the late 1800s, the word ampersand also became a slang term for “rear end, posterior, or the buttocks.” Over time, the & glyph was de-classified within the alphabet, its usage decreased, and today is often frowned upon when used in modern writing.
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