You (I) learn something new every day. Dropped across this while drifting about Google The ampersand (&) used to be part of our alphabet. Came at the tail end after Z. Worth reading this little explanation.
Link.
'The word “ampersand” came many years later when “&” was actually part of the English alphabet. In the early 1800s, school children reciting their ABCs concluded the alphabet with the &. It would have been confusing to say “X, Y, Z, and.” Rather, the students said, “and per se and.” “Per se” means “by itself,” so the students were essentially saying, “X, Y, Z, and by itself and.” Over time, “and per se and” was slurred together into the word we use today: ampersand. When a word comes about from a mistaken pronunciation, it’s called a mondegreen.'