via shady characters
“Although the ampersand’s creator (if it can be said to have one at all) is not recorded, there exists a popular misconception that the symbol’s name is taken from ‘Amper’s and’, after a supposed originator. Mentions of this derivation come from sources as diverse as an 1883 book on Personal and Family Names written by one H. A. Long, and more recently the collaborative, internet-based Urban Dictionary which suggests that the symbol was both invented by and named for a 17th century typesetter called Manfred Johann Amper. Unfortunately, both claims are undermined by a lack of corroborating evidence, and even more telling, ‘Manfred Johann Amper’ appears to never have existed.
The real origin of the word ‘ampersand’ likely owes more to Latin than to French, although it is a far more recent creation than the character which bears its name. During the 19th century, the ampersand was routinely taught as the twenty-seventh letter of the alphabet, and in common with those other letters which formed words by themselves — ‘A’ and ‘I’, for example — it was prefixed by the Latin per se, or ‘by itself’. Schoolchildren would recite “X, Y, Z, and per se and”, while particularly bored pupils would not so much recite as slur the final syllables to yield any one of a dazzling variety of words. This entry from Farmer & Henley’s 1905 Dictionary of Slang and Colloquial Engish recorded some of them for posterity:
Ampersand. 1. The posteriors. 2. The sign &; ampersand. Variants: And-pussy-and; Ann Passy Ann; anpasty; andpassy; anparse; apersie (a.v.); per-se; ampassy; am-passy-ana; ampene-and; ampus-and; am pussy and; ampazad; amsiam; ampus-end; apperse-and; empersiand; amperzed; and zumzy-zan...”
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