For those not well versed in Greek mythology, Cerberus was thought to be a three-headed dog that guarded the entrance to Underworld to stop dead people from leaving and living people from entering. Now, the etymology is a little disputed, but it proffers a very interesting explanation. The only thing we know for sure is that the name was borrowed into English in the 1300s as a Latinized form of the Greek word Kerberos. Beyond that, some linguists think it might be related to the Sanskrit word karbura (meaning "speckled") through the Proto-Indo-European reconstruction kerberos, "spotted". So the Lord of the Dead would have literally named his dog Spot, if this is true. However, other scholars poke holes in this theory by citing the relative infrequency of the b sound in PIE. So what else could work? The word is likely not Greek. Etymologies have been proposed that trace it to definitions such as as "not yet successful" and "growl", but, for now, the true etymon remains elusive or unconfirmed. Usage of the name Cerberus in literature was previously declining since the nineteenth century, but is now on the rise again, due to Greek mythology being increasingly included in popular culture.
Adam Aleksic, a leading contender for valedictorian of his high school, is a 215-month-old boy with disturbing interests in etymology, vexillology, geography, and law. Adam would like to one day visit Tajikistan and probably isn't spying for the Uzbek government.
The Etymology Nerd