Creating Hidden Administrative Accounts in OS X From Terminal
If you are sharing a computer, you may not want everyone who uses your computer to see your username in the login window or in the Fast User Switching menu. MacIssues points out that to hide your name, you just need a little terminal skill.
The idea here is to hide your administrator account so that no one even knows they need to be contacted. If you are using OS X Yosemite or higher, you can hide your username quite easily. Just run this command replacing your username with USERNAME :
sudo dscl. create / Users / USERNAME IsHidden 1
This will hide the administrator account from the login window, user and group settings, and the user switching menu, although you can still log in manually. For most of us, this is not really necessary, but if you have many different users on a shared computer, this is a good way to make it harder for people to tinker with your settings.
How to Create Hidden Administrative Accounts in OS X | MacIssues