How to remove eBay from the Menu Bar

If you mean the menu bar in macOS, two options. 1) System Settings > Menu Bar, scroll down to the Allow in the Menu Bar section and turn it off, or 2) hold the Command key, click the icon in th eMenu Bar and drag it off.

But, if you mean the tab bar in Safari, secondary click (control-click, two finder click) on that tab and select Close Tab.

if you mean the shortcut in the tabs, then have you tried to right click on it and delete/remove it?

Nicely done!