Kebab case is a way of writing phrases without spaces, where spaces are replaced with hyphens -, and the words are typically all lower case. The name comes from the similarity of the words to meat on a kebab skewer. It’s often stylized as “kebab-case” to remind the reader of its appearance.

Kebab-cased words are often simply referred to as hyphenated.

MDN: Glossary, Kebab case