Kids' cartoons have gone through different eras of what could and couldn't be shown on children's television. Standards have gone back and forth over the years, but for the most part there's a pretty clear line on what is deemed inappropriate for kids. That said, it hasn't stopped writers, animators, background artists and creators from sneaking in some adult jokes every now and then. With the modern age of streaming and rereleases of classic cartoons, lots of adults get to go back and watch their favorite cartoons from when they were little. Further, a lot of modern cartoons are written with both adult and kid audiences in mind. Wether old or new, these cartoons are rife with adult humor hidden beneath the surface.

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We're not talking about almost-curses or silly background signs either, some cartoons have really pushed the envelope by sneaking in some really raunchy stuff. A lot of these jokes are sexual innuendo, which are probably why they get past the networks, since kids probably won't pick up on the joke. Regardless, kids cartoons are surprisingly dirty if you look in the right places, which is why CBR decided to do some digging and find some of the absolute dirtiest adult jokes hidden in kids cartoons.

15 RUGRATS - GRANDPA'S SPACE PORN

Rugrats Space Vixens Joke

Rugrats is almost always referenced among '90s kids as a cornerstone of their childhood, and with good reason; it's a classic. But just because the show is beloved, doesn't mean it's squeaky clean. The show was known for a lot of adult humor that would go right over kids' heads, much like it does over the infant protagonists.

Amongst the many adult jokes in Rugrats, one stands out, a bit that paints Grandpa Pickles as a lonely old pervert. When Grandpa is babysitting the kids, he rents them some movies to watch, mostly Reptar flicks, but one is different from the others. Grandpa has saved a movie for after the kids go to bed, a movie suggestively entitled "Lonely Space Vixens." Yes, that's right, Grandpa was planning on watching alien-themed porn as Tommy and Chucky slept. Excuse us while we shudder.

14 ANIMANIACS - FINGERPRINTS

Animaniacs Prince

You knew this one was coming, since it's perhaps one of the most brilliant, if not the most brilliant uses of dirty wordplay pop culture. The Animaniacs, being a tribute to classic Looney Tunes and other old slapstick animation, was known for two things, an absurd amount of old-Hollywood references and lots of adult jokes.

The most famous dirty joke on the show, that somehow got put on the air, originates from the 25th episode of the first season. In the segment titled "Hercule Yakko," the Warner siblings parody an Agatha Christie story as they search for a stolen diamond. When Yakko says to search for prints, Dot later comes back carrying pop star Prince in her arms. Yakko says to this "no no no, fingerprints," to which Dot replies, looking directly at the musician, "I don't think so." It's as brilliant as it is dirty.

13 SPECTACULAR SPIDER-MAN - SPIDEY'S "GOOP"

Spectacular Spiderman and Black Cat

Often credited as the greatest Spider-Man cartoon of all time, Spectacular Spider-Man blended comedy, drama and action perfectly while sporting an incredibly unique animation style via character designer Sean "Cheeks" Galloway. The show gave streamlined and updated versions of our favorite Spidey characters and storylines, but was unfortunately cancelled after two seasons, leaving lots of loose threads.

Amongst the 26 episodes of the series, there was one rather gross double entendre during Spider-Man's first encounter with the Black Cat. As Spidey shoots webs at the criminal to stop her from stealing the (at the time) unidentified Venom symbiote, she playfully says "you better not get your goop in my hair." If it wasn't clear enough what she was implying, Spider-Man replies with "don't worry, it comes off with ice or peanut butter."

12 ED, EDD N EDDY - EDDY'S "SUPPLIES"

Ed Edd and Eddy Tissues

After a 10-year run, Ed, Edd n Eddy stood as the longest running Cartoon Network original series at the time of its end. Throughout its run, the show had a TON of adult humor hidden under the surface, most likely due to the fact that creator Danny Antonucci was dared to make a kids' show after being an adult cartoonist for so many years.

One of the dirtiest background jokes comes in the episode "The Day The Ed Stood Still," in which Ed dresses up as a monster and terrorizes the cul-de-sac. At the end of it, the Ed's hang out under Eddy's bed —where he keeps "supplies" — to hide from the angry victims of Ed's shenanigans. Some of these supplies include nudey mags and balled up tissues. We'll let you figure that one out.

11 THE NEW BATMAN ADVENTURES - HARLEY'S DESIRES

BTAS_Rev_Harley

Everyone loves Batman: The Animated Series as well as the sequel series The New Batman Adventures. Both are regarded as the best iterations of Batman and stand on high pedestals of animation and storytelling praise. Though the shows were never meant to be tied to one age range, they still had to stick to kids cartoon parameters, though the crew definitely snuck in a few snippets of adult humor.

In the episode "Mad love," which was originally a comic, Harley seeks to destroy Batman so that The Joker's attention can be focused on her and her alone. In the very beginning of the episode, Harley's love of The Joker is displayed by her sexy night gown and downright horniness as she attempts to seduce Joker, going so far as to say "Don't you wanna rev up your Harley?" She sure gets right to the point, doesn't she?

10 JUSTICE LEAGUE - FASTEST MAN ALIVE

Justice League Flash

Yet another pinnacle of modern animation, Justice League has a huge following both on its own and as part of the DC animated universe. In the original show, prior to the Unlimited series, there were seven core members of the Justice League: Superman, Batman, Wonder Woman, Martian Manhunter, Hawkgirl, Green Lantern and of course The Flash.

The scarlet speedster of this world is in fact Wally West rather than Barry Allen. The Flash serves as the comic relief of the team and the fast-talking smart-mouthed nature of Wally fits this role perfectly. During one of the character's many braggart moments, specifically in the episode "Injustice For All," The Flash boasts his title as "the fastest man alive." Hawkgirl, crisply and bluntly, shoots Flash down with a simple "which might explain why you can't get a date." Damn, Shayera, that's some serious shade.

9 ROCKO'S MODERN LIFE - "SPECIALTY" PHONE OPERATOR

Rocko on Phone

Like a lot of cartoons of the time, Rocko's Modern Life had a lot of content for adult audiences to enjoy, and the premise of the show on its own feels like a late-night sitcom. Yet, since the show was on Nickelodeon, it's surprising how much adult humor leaked through the cracks.

One of the most famous examples of this is in the episode "Canned," in which Rocko loses his job and must find a new one. While searching the newspaper for work, Rocko comes across an opening for a "speciality phone worker." When Rocko tries it out, his work station has a sign that says "Remember: be hot, be naughty, be courteous," and he answers the phone with "oh baby, oh baby, oh baby." Clearly, Rocko took a job as a phone sex operator, much to the disgust of his neighbor Mrs. Bighead, who calls the hotline.

8 BATMAN: THE BRAVE AND THE BOLD - BIRDS OF PREY

Birds_Of_Prey

Now this is a fun one, and from a fun series. If you haven't check out Batman: The Brave and the Bold then you're missing out on some cheesy, over-the-top Batman '66-esque zaniness. The show was known for classic-styled superhero storytelling as well as throwing the occasional musical number in for good measure. One of these songs is a tremendously inappropriate performance by the Birds of Prey: Catwoman, Huntress and Black Canary. Seriously, watch it right now.

Pretty raunchy right? Not only are the Birds of Prey dancing pretty suggestively while showing of some serious cleavage (it helps them fight crime?) but also those lyrics are insane. The song is nothing but jokes at the expense of various other superheroes in the form of innuendo suggesting their sexual shortcomings. Seriously, how did this get on Cartoon Network?

7 HEY ARNOLD - GRANDPA'S WILD YEARS

Hey Arnold Grandpa Woodstock

This one is one of the only non-sexual dirty jokes in here, though Hey Arnold! has its fair share of innuendo amongst it's five seasons. This adult joke is presented to us in the episode entitled "Back to School" in which Arnold learns that his Grandpa never finished grade school, something he was almost too ashamed to admit.

This news comes after Grandpa fails to help Arnold with his homework. Grandpa is down on himself about never finishing the 4th grade and says he's "lost too many brain cells" to go back to school. Arnold cheers him up by saying "you've still got plenty of brain cells." Grandpa nonchalantly replies with "no, not since woodstock." Seems like Phil had some drug-heavy hippie days in his youth.

6 FREAKAZOID - MEAT LOVER

Freakazoid Meat Joke

Freakazoid was known for being a wacky, zany and overall surreal parody of superheroes, featuring a character as insane as the Joker, but with all the heart of Spider-Man. While the show and character did result in some controversy over it's similarity to Mike Allred's Madman, Freakazoid is still a beloved cartoon of the'90s.

Amongst the bizarre, cartoony and oddball humor was a good collection of sexual innuendo and adult jokes. One of these came in the form of a conversation between Freakazoid and his "sidekick" Sgt. Cosgrove, a character voiced by and based on Ed Asner. In this conversation, Freakazoid asks Cosgrove why he isn't married, to which he answers "I like meat too much." Perhaps Cosgrove just really loves meat products, but Freakazoid still replies with "you could be married and still eat a lot of meat." Freakazoid sure is one open-minded fellow.

5 JOHNNY BRAVO - THE WHOLE SHOW

Johnny Bravo

It's so hard to imagine how the pitch for Johnny Bravo went when creator Van Partible was selling the idea to Cartoon Network, since the show was about the titular character as he tries to get women to "date" him. Johnny is usually unsuccessful however since, while he's muscular, he's not exactly a smooth talker, plus he still lives with his mom. Most adults knew that "dating" for Johnny actually meant "one night stands" and the show's adult humor plays off of this, with the slapstick and zany situations were hooking in the actual target audience.

It's not surprising that Johnny Bravo helped launch the career of adult sitcom mogul Seth MacFarlane, since the show was rife with sexual humor and innuendo. Everything from Johnny's creepy and borderline harassing pickup lines to asking a teenaged girl what she's wearing over the phone proves just how dirty the show really was.

4 DEXTER'S LABORATORY - DANCING IS $50 EXTRA

Dexter's Lab Candi

Before there was Samurai JackGenndy Tartakovsky's definitive masterpiece, there was Dexter's Laboratory. The show had a simple premise, Dexter is a boy genius who has a secret laboratory. Dexter would get into various shenanigans involving his inventions or the annoying interference of his older sister, Dee Dee.

In one particular episode entitled "Dee Dee and the Man," Dexter has had enough of Dee Dee and fires her from being his sister. Though Dexter ends up getting more work done, he finds something is missing from his life, so he hires a new sister, an actress by the name of Candi. Candi is a beautiful curvaceous woman who Dexter pays to dress and act like Dee Dee, including dancing like her. However, when Dexter asks this of Candi, she says "Okay, but it's fifty bucks extra," a subtle hint that Candi might not exactly be an "actress."

3 POWERPUFF GIRLS - PENCIL SHARPENING

Power Puff Girls Miss Bellum sharpening pencil

The Powerpuff Girls is often credited with strong and diverse depictions of female characters within the six seasons of the original series. Of those characters, Ms. Bellum stands as one of the best characters besides the Powerpuff Girls themselves. Ms. Bellum is the tall, buxom, beautiful and most of all intelligent secretary to the Mayor of Townsville. Ms. Bellum is far more competent than the mayor and pretty much runs the city for him.

Perhaps this is the reason why villain Sedusa impersonates the secretary in the episode "Something's a Ms." While posing as Ms. Bellum, Sedusa, true to her name, very suggestively assists the Mayor with his broken pencil. The villain very delicately takes the Mayor's hand, still holding the pencil, and slowly pushes it into the pencil sharpener, which appears to bring the Mayor great ecstasy. When he pulls the pencil out, it's short and stubby. Subtle, real subtle.

2 REGULAR SHOW - "SODAS"

Regular_Show_Sodas

Regular show is one of the many modern cartoons that has an adult audience in mind. In fact, the whole premise of the show seems like it should be aimed at 20-somethings since it since it follows two 20-somethings in a dead-end job as they goof off and avoid growing up. Of course, the show is far from regular since pretty much every time Mordecai and Rigby avoid responsibility, they get into some kind of wacky supernatural predicament.

A constant among these shenanigans is the fact that the two best friends constantly party, usually drinking mass amounts of "soda." We put that in quotes since every time Mordecai and Rigby partake of these "sodas" they tend to get rowdy, act stupid and make rash decisions that they forget the next day. Sounds like "soda" might actually be a brand of beer if you ask us.

1 SPONGEBOB SQUAREPANTS - SEA PORN

Spongebob_Sea_Anemone

At over 200 episodes, Spongebob Squarepants is by far the most successful children's cartoon franchise out there. The series has spawned video games, comic books and shelves upon shelves of merchandise. With the show lasting as long as it has, the series has seen some criticism, both because of the declining quality over its 10 seasons and because of various controversies in episode and tonal themes.

Regardless, the show has managed to sneak in some adult humor without controversy, usually in a playful manner. One of these playful jokes comes when Spongebob is watching a rather alluring video of a sea anemone dancing on TV. When Gary enters, Spongebob quickly changes the channel, implying that the video was something to be ashamed of, perhaps even sexual considering the similarities of anatomy between sea anemones and sea sponges, wink wink.