passwd
AccountsPackage: passwd
Changes a password, or locks an account with -l without deleting it. Locking closes neither the open sessions nor SSH key access: those are two other decisions.
What its options do in the lessons
From the same glossary the lessons render under their commands, so the two cannot disagree.
passwd -l- Locks the password by prefixing it with
!, the same operation asusermod --lock. The account itself stays open: an SSH key keeps working. passwd -S- Reports the password status without changing anything: the name, then
L(locked),P(usable) orNP(none), then the date of the last change and the four periods from/etc/shadow. It says nothing about the account expiry date.