"default" watchdog device - ?

Hi guys. Without explicitly, manually using watchdog device for a VM, the VM (centOS 8 Stream 4.18.0-365.el8.x86_64) shows '/dev/watchdog' exists. To double check - 'dumpxml' does not show any such device - what kind of a 'watchdog' that is? watchdog-5.15-2.el8.x86_64 on such a VM does not seem to do anything with it. Host is centOS 9 with: qemu-img-6.2.0-11.el9.x86_64 libvirt-daemon-8.0.0-5.el9.x86_64 many thanks, L.