What character was once considered to be the 27th letter of the alphabet?

The story behind the answer

Ampersand is correct because “&” was once taught in English primers as the 27th letter. Children ended the alphabet chant with “X, Y, Z, and per se and” (meaning “and, by itself, ‘and’”). Over time, that phrase slurred into the word “ampersand.” So the symbol wasn’t just punctuation—it was part of the alphabet sequence.

The ampersand began as a ligature of the Latin word “et” (meaning “and”), which explains its looping form. By contrast, the pilcrow (¶) marks paragraphs, the interrobang (‽) is a modern combo of question and exclamation, and the tilde (~) is a diacritic or approximation mark. Memory tip: think “and-per-se-and” → ampersand → the “and” symbol that used to cap the alphabet.