Q: mac with el Captain  have a icon in launchpad called Citrixonlinelauncher.  How to remove the turn thing.  Have no idea how it got there

Hold the "Option" key, and an (X) should appear.  Click the (X) and that should remove the item

The "Option" key

Before holding the "Option" key:

After holding the "Option" key:

A google search reveals this  http://www.shouldiremoveit.com/Citrix-Online-Launcher-78358-program.aspx

That program is bundled with GoToMeeting. I would imagine if you uninstall GoToMeeting, the CitrixOnlineLauncher will go with it.

Opening it won't allow you to erase it.

Some apps have embedded app that show up in LaunchPad. The only way to remove them is to remove the app that installed them. You need to look for an app that creates something like goToMeeting or VPN. It uses Citrix to work its magic, so you need to find the app you installed that has that embedded.