The X-Men’s greatest threat in the current era of Marvel Comics is easily the super Sentinel Nimrod, as it is a machine that is adaptable, nearly impossible to kill, and grows more intelligent every day. This makes it a little odd that the villain’s name is another word for "idiot." Originally, the name "Nimrod" was far from associated with "idiot," but because of the unintended sociological consequences of a joke that evidently failed to land with an intended audience, the name’s meaning completely changed.
X-Men’s Nimrod was always a serious threat to the mutant team since the villain’s inception, but it wasn’t until the start of the new mutant era within Marvel Comics that Nimrod was really considered their greatest foe. House of X and Powers of X by Jonathan Hickman, Pepe Larraz, and R.B. Silva laid the groundwork for the new age of X-Men, as well as the introduction of a familiar yet previously underutilized villain: Nimrod. Nimrod is the cause of the end of mutantkind in a number of alternate futures experienced by Moira MacTaggert. While not the main focus of every major X-Men story after House of X/Powers of X, Nimrod is the looming threat that will either be vanquished by the X-Men, or live long enough to be the reason behind the mutants’ extinction.
Singlehandedly bringing about global genocide is a tall order for any villain, especially a Sentinel with a foolish name. Though as it turns out, Nimrod’s name is actually one that is perfectly fitting. Nimrod shares a name with the Biblical hunter, Nimrod, who was said to be a mighty hunter before the Lord. Like the Biblical Nimrod, the Sentinel is a great hunter, but of mutants, and proves time and again to be the best there is. So, since Nimrod is the name of the Bible’s greatest hunter and is therefore the perfect name for the X-Men villain, why do people associate the name with an insult on someone’s intelligence? Weirdly enough, there is one theory that blames the phenomenon on none other than popular cartoon series, Looney Tunes.
Whenever the hapless hunter Elmer Fudd attempted to hunt Bugs Bunny and Daffy Duck, the troublemaking duo would call him "Nimrod" in the same way one would sarcastically call someone "Einstein" when they did something silly. Since Looney Tunes was a show geared towards a younger audience, it is possible that kids didn’t fully understand the reference Bugs was making, but followed the chain of logic associated with the fact that "Nimrod" was clearly an insult. This possibly led to the incorrect conclusion that the Biblical hunter’s name was just another word for "doofus."
Because of the popularity of Looney Tunes, the misunderstood reference was able to take hold for generations of viewers who were more than likely not as familiar with the Book of Genesis as they were with the misadventures of Bugs Bunny and Elmer Fudd. This theory suggests that due to the widespread misunderstanding, "Nimrod" officially became another word for "idiot." X-Men evidently did not consider the public perception of the name before coming up with the villainous Sentinel’s title as the creative team behind Nimrod’s creation assuredly intended for the mutant-hunting android to be named after the Biblical hunter of the same name. However, seemingly because of the confusion created by Looney Tunes, X-Men unintentionally named its biggest villain after another word for "idiot."