Is there a more iconic cartoon character than Nickelodeon's SpongeBob SquarePants? Probably not, with twenty plus years on the air, the show is stronger than ever. Every decade Bikini Bottom and its residents are introduced to a new generation of loyal fans.

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While SpongeBob is one of the more kid-friendly cartoons on the air these days, there still are some moments and references that have flown past children's heads. At least, until they become adults and understand the hidden meaning. These moments are what keeps it fresh, able to connect with a larger audience, and different age demographics. So what are the 10 funniest quotes off of SpongeBob SquarePants that only adults understand?

Be Assertive Not Insertive

When one thinks of sex jokes, SpongeBob probably doesn't come to mind, but, surprisingly enough, fans could make a long list of sexualized jokes SpongeBob has made over the years. In the SpongeBob SquarePants episode "Walking Small" Plankton teaches SpongeBob how not to be bullied by others. While sitting on a bench, a larger fish sits on SpongeBob, causing Plankton to tell him to be assertive. SpongeBob proceeds to stick his hand in and out of the guy's pocket. A visibly frustrated Plankton tells him to be assertive, not insertive.

The French Tickler

In his quest to be a better karate master than his karate instructor and partner Sandy, SpongeBob accepts a request to go to Karate Island, which is just a condo scheme, centered around karate. However, when SpongeBob must face off against a villain to get to the next level, he comes across a Frenchman, who has an iron tickler device that looks like hands. Upon meeting SpongeBob The Tickler states: "You cannot pass unless you defeat me, The Tickler, and my iron-finger style." That joke just sounds dirty no matter how old you are.

The Sport's Channel?

SpongeBob fans will never watch an underwater nature documentary the same way again after watching this episode of SpongeBob. As SpongeBob was flipping through channels, he comes across a sea anemone dancing to provocative sounding music.

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SpongeBob gets on the edge of his seat with his eyes bulging, clearly glued to the television. At least until the moment, Gary enters the room and he claims he was just looking for the sport's channel. It doesn't take a grownup to realize that what he was watching wouldn't be found on ESPN.

Lick What!!!

In the 2001 episode entitled "I'm Your Biggest Fanatic" SpongeBob catches jellyfish using the power of music along with gobs of jelly that he smears on his face. The jellyfish licking the jelly off of SpongeBob's face seems innocent enough but, then, he comments "who wants to lick my cheeks" an image of SpongeBob's bare bottom at the beginning of the episode appears in viewers' minds. Making this all too cheeky joke sound dirtier than the writers might have intended. Either way, it is a priceless moment that SpongeBob fans still giggle about.

The Period Comment

When it comes to juvenile comedy, a few kind of jokes are usually expected. These include butt jokes, fart jokes, and fat jokes. Period jokes, however, are usually either nonexistent or extremely rare. Yet, that didn't stop Squidward from going there. When Plankton appears in a giant red blimp, hovering over the Krusty Krab, Mr. Krabs asks if he is seeing things. Squidward replies that it appears to be that time of the month again. Is it the bottom of the barrel kind of joke? Of course, but you got to give the writers props for bravery.

SB + PS = CLAM

In the SpongeBob SquarePants episode "Rock A Bye Bivalve" SpongeBob and Patrick are tasked with taking care of a baby scallop that they found in a coral reef. The episode is filled with adult situations and references throughout, but the funniest involves a thought bubble by a passing fish couple who see SpongeBob and Patrick pushing a baby carriage with the baby scallop in it. It shows a sponge plus a star equals a scallop. Fans can ponder what that infers, but the act it is hinting at is obvious.

Suicidal Medieval Host

In the episode "Dunces And Dragons" SpongeBob and Patrick attend Medieval Moments Stadium to watch a jousting tournament. They are greeted by the less than enthusiastic host dressed in medieval garb and holding a sword.

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He welcomes them to the tournament and assists them in finding their seats. Once they are out of sight, he holds the sword to his throat saying "someday...but not today" before finally putting the sword down. Working a humiliating job at a medieval restaurant, while being forced to carry around a toy sword must not have been where he saw himself working ten years ago.

Sentence Enhancers

After SpongeBob reads unfamiliar words on the side of a dumpster at the Krusty Krab, Patrick tells him they are "sentence enhancers" causing SpongeBob and the rest of the cast to curse like sailors for the rest of the episode. When Squidward tells Mr. Krabs there are only 7 bad words that are not appropriate in a business setting, Mr. Krabs tells him "Not if you're a sailor." After Mr. Krabs stumps his toe on a rock, he then proceeds to go on a bleeped out tirade that lets fans know there are more than 7.

Don't Drop The Doubloons

Surprisingly enough, the "sentence enhancer"episode didn't even come close to providing fans with provocative adult humor when compared to Gary's bath scene. When trying to clean up a dirty Gary, SpongeBob takes soap out of the bathtub. He then proceeds to show them to Gary, explaining to "not drop the doubloons" while winking. It was an obvious reference to the more well-known phrase to not drop the soap, especially when in a prison shower. Pretty sure Gary understood what he was talking about even without the obvious wink at the end.

Coin Slot

In the episode "My Pretty Seahorse" SpongeBob finds a seahorse and immediately, and stupidly, wants the wild animal as a pet. He does manage to tame the creature but when he takes it to work, things go a bit awry. After tying it outside the Krusty Krab, two fish believe it to be a kid ride. One pulls out a coin, searches for a little while before proclaiming "I can't find the coin slot...here it is" before then being kicked out of the scene by the violated and offended seahorse.

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