Furball had become part of the family, but as yet had no name(other than occasional "Dammit!" and other references). So one evening wife and I were going over possibilites and inspiration struck.
A while before we'd discovered the Asterix the Gaul comics. If you've not heard of them, there's this village in Gaul. The only village not conquered by the Romans. It seems the village druid Getafix can brew a potion that gives super strength and speed, and every time they've been attacked the Romans(pirates, whoever) get their ass kicked, so the local Roman garrison has a "We leave them alone and they don't hurt us" attitude. The village has, among others,
Asterix, the best warrior in the village
Cacofonix the (untalented) bard
Fulliautomatix the blacksmith
and the best friend of Asterix, Obelix. Who is permanently strong and fast because as a baby he fell into a vat of the potion, and has a dog named(what else?) Dogmatix.
So I said "Let's call him Catmatix. It's simple, and when I yell "CAT!" he'll know who I'm talking to." And, since he could make an amazing amount of noise running through the house and on occasion had caused minor disasters, wife extended this to Catmatyx(yeah, different spelling) Catastrophix the Curious called Calumph.
Never used the full name except around friends; in any case, that's how the beast was named.