Little labeling change that aligns with GitHub's nomenclature:

Secret gists don't show up in Discover and are not searchable unless you are logged in and are the author of the secret gist. Secret gists aren't private. If you send the URL of a secret gist to a friend, they'll be able to see it. However, if someone you don't know discovers the URL, they'll also be able to see your gist. If you need to keep your code away from prying eyes, you may want to create a private repository instead.

Source: https://docs.github.com/en/get-started/writing-on-github/editing-and-sharing-content-with-gists/creating-gists