"consisting of the shell's path, relative to root." we could make this easier to understand by saying: "consisting of the shell's absolute path." in addition, an Example would say more than a thousand words.
<https://man.freebsd.org/cgi/man.cgi?query=shells&sektion=5&manpath=freebsd-release> Maybe a candidate for a simple pull request; <https://github.com/freebsd/freebsd-src/blob/main/CONTRIBUTING.md#contribution-guidelines-for-github>.