The dot above a lowercase 'i' or 'j' has its own name: a tittle.

The small dot that sits above a lowercase “i” or “j” in the Latin alphabet is formally called a tittle. The term comes from Latin “titulus,” meaning a small mark or superscript sign, and made its way into English by the medieval period, appearing notably in early English translations of the Bible in the phrase “jot and tittle” to mean the smallest possible detail.

Tittles aren’t just decorative. In handwriting and certain typefaces, the dot helps distinguish “i” from other narrow vertical strokes in adjacent letters, which is why it survived as lowercase Latin script evolved. Some languages that use a modified Latin alphabet, such as Turkish, even distinguish between dotted and dotless versions of the letter I as entirely separate letters with different sounds, treating the tittle as meaningful rather than cosmetic.