Friends isn’t really that old, but it is already considered a classic television show. There are lots of jokes on the series that are pretty much timeless, and lots of them are very clever as well.

While many of the jokes that were featured on the show were really obvious, some of them were a little bit harder to figure out. Those who have watched the show multiple times might never get bored with it, since many fans have found out the meaning to jokes that they did not understand before.

A good example of one of those jokes is in the episode called “The One With Ross’s New Girlfriend.” Phoebe gives Monica a haircut that makes her look like actor Dudley Moore, and Chandler says it looks like a 10, which is a reference to one of Dudley’s most famous films, 10. Here are a few more of the jokes that went largely unnoticed on Friends.

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Rachel’s Haircut

In an episode called “The One With The Lesbian Wedding,” Rachel Green makes a joke about her hair, and despite how funny this joke really is, it didn’t seem to get much attention. In this episode, Rachel’s mom visits her and delivers some pretty devastating news.

Mrs. Green tells her daughter that she has made plans to break up with her father, and that she wants to live like Rachel. Later on in the episode, Rachel suggests that her mother could have just got a similar haircut, which is funny because many Friends fans wanted to get “the Rachel” haircut.

The Reference To 'Of Mice And Men'

In one episode, Chandler gets worried that Joey will accidentally cause harm to an animal, so he makes a reference to the book Of Mice And Men, and it seems that some viewers didn’t get the joke. This episode is called “The One With The Chick And The Duck.”

Joey becomes convinced that he and Chandler need a chick, which leads to him bringing one home. In one scene, Joey is talking to Phoebe while he holds the chick, and Chandler refers to him as “Lennie.” In Of Mice And Men, there is a character named Lennie who accidentally harms his pet.

The Joke About The Mime

In “The One With The Prom Video,” Chandler makes a joke about a mime that was named Marcel Marceau. Joey gets him a friendship bracelet, but the problem is that he feels as though the bracelet is really ugly, which leads to him venting to Phoebe about it.

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Joey catches the two of them, and he is visibly upset about it. Chandler then tries to get Joey to believe that they were doing impersonations of other people, and he suggests that Joey do his impersonation of Marcel Marceau. Joey does not say anything, and he walks away. Marcel was a mime, which is what makes the whole thing as funny as it is.

Joey Forgot His Pin Number

In “The One In Vegas: Part 1,” Joey reveals what his ATM pin number is, which is a pretty intelligent joke that no one seemed to pick up on until recently. Joey speaks with Phoebe on the phone, and he tells her that he needs his ATM pin number since he forgot what it is.

Joey left it scratched on the side of a nearby ATM machine, and Phoebe asks him if it is “5639.” He tells her it is, and then he thanks her, but the joke is that 5639 spells out Joey’s name on a dial pad. His pin number was literally his first name, and he still forgot it.

There’s A Reference To A Sally Field Movie

Rachel gets worried that one of her co-workers will try to take her job away from her, and when she is talking this over with Ross, she makes a reference to a Sally Field film called Norma Rae. After she goes on maternity leave, she decided to cut things short and return to her job because she was worried that someone else was going to take it, and she lies to Ross and claims that she will get fired if she doesn’t go back soon. He then tells her what he’s going to do if that happens, and she refers to him as “Norma Rae” after telling him to calm down. Norma Rae is about a woman who gets her co-workers to form a union.

What’s Written On The Chalkboard Behind Ross’s Head

At the beginning of an episode called “The One With Rachel’s Book,” there are some funny things written on a chalkboard behind Ross’s head while he is teaching a class. This is easy to miss, since it’s not something that is very noticeable unless viewers are looking for it, but once someone knows about it, it’s definitely something that is hard to ignore. Some of the things that are written on the board suggest that Ross wants to use the DNA from a mosquito to create a T-Rex, which is funny because he is telling his students that he was the first person who had the idea for Jurassic Park.

The Spanish Joke

Rachel And Her Mother

In the episode called “The One With The Baby Shower,” there is a pretty obvious Spanish joke that is very funny. During Rachel’s baby shower, she and her mother are having a talk about how hard it is to raise a child.

Mrs. Green suggests that Rachel hire a nanny, and then they start talking about the nanny that Rachel had when she was growing up. Her name was Mrs. Kaye, and she taught Rachel a little bit of Spanish. Rachel mentions the fact that the nanny was really nice, and she recalled the nanny teaching her to say “Tu madre es loca.” In English, that means she was telling Rachel her mother is crazy.

Chandler’s Line About A Q-Tip

Chandler makes a joke about a Q-tip, which basically implies that Joey has been damaging his ears. In the episode called “The One With Ross’s New Girlfriend,” Chandler needs a new tailor, and Joey suggests that he use the one the Tribbiani family uses.

Joey has a hard time remembering how long he has been going to that tailor, which is why Chandler tells him to stop pushing Q-tips further into his ears when he feels resistance. This joke suggests that Joey has been going so far he's actually damaging his brain, and the fact that he doesn’t deny it only makes it even funnier. Actor Matthew Perry, who played Chandler Bing, claimed that this was his favorite joke to tell on the show.

Carol And The Hair

The episode called “The One Without The Ski Trip,” Ross’s ex-wife, Carol, can be seen removing a hair from her mouth, and this is probably one of the most underappreciated jokes in the entire series. Ross stops by the apartment that Carol Willick shares with her wife, Susan Bunch.

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His arrival seems to have interrupted something very important between Carol and Susan, since she can be seen trying to take a hair out of her mouth, and she is wearing a bathrobe. The idea for this joke came from actress Jane Sibbett, who played Carol. “That was the only time I pitched something that was really outrageous and it actually got on air,” said Sibbett.

Rachel Makes Bad Coffee

Most of the jokes about Rachel’s terrible coffee-making skills are very obvious, but the one where her coffee kills a plant went largely unnoticed. In the first episode of Friends, Rachel is still getting used to doing certain things herself, and she attempts to make coffee for the first time (which might have foreshadowed her future job at Central Perk), and she serves some to Joey and Chandler.

They’re happy about it at first, but then they discover that it has a terrible taste, and they get rid of the coffee by pouring it into a plant. The plant is dead later on, which means that Rachel’s coffee was so bad it killed the plant.

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