Here’s a quick reference table of ls flags relevant to security (updated from common 2021 cheat sheets):
Some developers create aliases like alias filedot='ls -la | grep "^\."' to list hidden dotfiles. In that context, ls filedot 2021 could be someone’s personal shorthand to list dotfiles modified in 2021—but that would require a custom script, not a built-in command. ls filedot 2021
Or more simply, if she was sure she was in the right directory and just wanted to see if there were any files from 2021 with "filedot" in their name: Here’s a quick reference table of ls flags