Note: this will take you to Citrix's website to download the latest installer.
Drag Applications > Citrix Receiver.app into the trash.If you have older versions of Citrix software installed, such as Citrix Receiver or Citrix ICA Client, you can remove them with these steps. If your password exceeds this age limit, you need to change your Kerberos password To use Citrix, your Kerberos password cannot be more than three years old. You may need to change your Kerberos password