The supporting characters of a sitcom can be just as important as the main characters. When it comes to Seinfeld, it's hard not to forget the rambunctious and comical displays by Frank Costanza (Jerry Stiller). The majority of his scenes in the show involve his interactions with his son, George.

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There are some golden moments between Frank and the other main characters that had audiences dying of laughter. Frank was certainly a character, regardless of who he was interacting with. Some of his best moments with the other characters range from fistfights, a drama surrounding a TV Guide and his own self-proclaimed holiday.

The Celebration Of Festivus

Festivus dinner in "The Strike"

Fans know that George's childhood wasn't exactly easy. In an episode entitled "The Strike," audiences and the main characters get an insight as to one of the reasons. To combat the pressures and commercialism around Christmas, Frank created his own holiday known as Festivus. Fans can even Google the holiday and learn all about it.

In the episode, fans get a joyous and social interaction between Frank and the gang at dinner. To kick things off, Frank starts with the Airing of Grievances. Frank claims he's got a lot of problems with everyone and they're forced to hear them. Then it's on to the Feats of Strength, to which even Kramer has to tell Frank that his holiday is a little too out there.

Franks Tells The Story of Festivus

Frank at Monk's Diner in "The Strike"

Frank first tells the meaning behind Festivus to Kramer at the bagel shop. He tells him it's important to tell people how much of a disappointment they were that year. Frank also mentions that he finds tinsel distracting. The scene then shifts to Frank and the Festivus pole at Monk's diner.

George gets clammy seeing the dreaded pole. Franks claims it's George's heritage and needs to embrace it. To top it off, Frank plays a past recording of their holiday to his son and Jerry. Frank claims to Jerry that they had a marvelous time.

Elaine Takes Frank's TV Guide

Frank inspects a TV guide in Seinfeld

Who would have thought that Frank would collect TV Guides? Even Jerry was shocked to discover it. Days later, Frank is still upset and ranting about Elaine coming into his house and taking it. Jerry comes to the rescue and gets her a new one to give back to Frank.

But along the way, she couldn't resist a gyro and gets stains all over the guide. It's comical when she arrives at the Costanza house and the first thing that Frank says is, "Why'd you take my TV Guide?" But he gets even more upset at Elaine that she didn't keep it in mint condition.

The Cabana Shirt

Frank and Kramer in "The Raincoats"

Frank gets into a couple of physical fights with Kramer. One of them is when Kramer visits the house in a new shirt. And it's not just any shirt, but Frank's cabana shirt. Frank soon realizes that it might be his and asks Kramer where he got it. In a fit of rage, he says it's his and even calls Kramer a "son of a b*tch."

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Frank wants it back and tries to physically take it off Kramer. And who's to blame but George. When learning that George sold it to Rudy, Frank thumps him on the head. When Mrs. Costanza mentions that she loves Kramer's shirt, Frank yells that it's his. It's comical because, in a prior scene, she said that she hated Frank's cabana wardrobe.

The Prophylactic Wrapper

Frank, Jerry and George in "The Cigar Store Indian"

The same TV Guide episode gave fans another nugget of joy from Frank. George is living at home and Mrs. Costanza finds a disturbing item in their bed. Frank is shocked to see the 'prophylactic wrapper' and Jerry sees this as his cue to leave. George decided to have intercourse in their bed because his bed was too small.

Frank says, "I'm gone two weeks and you turn my house into Bourbon Street?" As any parent would in his situation, he grounds George, despite him being a grown man. It's Franks' house, Frank's rules, and George violated those rules.

Kramer Stopped Short

Frank, Jerry and Elaine in "The Fusilli Jerry"

Another memorable tussle happens between Kramer and Frank in "The Fusilli Jerry." Kramer does a favor for Mrs. Costanza and drives her home after her eye lift surgery. When another driver hits the brakes, Kramer stops short and puts his arm out across her chest to keep her safe. She takes this as an act of flirting and Frank finds out.

Apparently, this was his go-to move when he was younger. Clearly upset, he goes to Jerry's apartment to find Kramer. Jerry and Elaine learn about his old moves and Jerry is intrigued. Kramer arrives and Frank gets in his face about his wife and his proclaimed title, "The Ass Man." They start a tussle, but Frank falls derriere first on Fusilli Jerry.

Elaine & The Nail Salon

Frank and Elaine in "The Understudy"

In "The Understudy," Elaine gets concerned when she thinks the workers at her nail salon are talking badly about her. But there's one problem, they all speak Korean. She finds a way to find out. During his time as a salesman, Frank would visit South Korea often and he learned the language.

Elaine takes him to get a manicure to eavesdrop on the workers. The workers start making fun of his sweater and make a remark about where his tail is. Frank's on to them and blows up, saying he heard every word they said.

The Cup Sizes

Frank and a bra in "The Sniffing Accountant"

Leave it to Mrs. Costanza to think that her son doesn't know anything about bras. Frank gets a job for George at a bra sales company. Frank bets on what the bra is made of and has his wife go get one of hers. In the meantime, Frank talks to Geroge about all the different cup sizes.

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Frank knows everything - from the A, the C, to the D. Frank inspects his wife's bra and breaks down its structure. The cups in the front, the hooks in the back and that's about it. The conversation is then over and George leaves the room.

The Bro Bra Or Manssiere

Estelle and George see Frank wearing a brassiere in Seinfeld

Speaking of bras, Kramer and Frank have one of the best interactions in the show in "The Doorman." Frank and his wife are going through a separation and Frank is living with George. Kramer goes to return his record player and notices that Frank has some baggage upstairs and recommends a solution.

The scene cuts to Kramer putting on 'The Bro' while they both dance to a record. Kramer adjusts the front just as George and Mrs. Costanza walk through the door. It's not an easy scenario to digest, but Frank is in love and feels 10 times younger. He and Kramer decide to go into business together.

Elaine & Frank's Police Station Fight

Frank and Elaine in "The Little Kicks"

George is in no way a bad guy, all the time, but he tries to catch the attention of an employee at Elaine's job and messes up, ruins his image, and is taken to the police station for bootlegging. Fans of the sitcom can agree that the small scene between Elaine and Frank at the very end of this episode is comedic gold.

Frank tells Elaine that there's no way that George could hatch such a scheme and Elaine agrees wholeheartedly. The scene escalates and Frank takes offense, saying, "You saying you want a piece of me?" Elaine claims she can drop him like a bag of dirt. Frank gets riled up and says if she wants a piece of him, she's got it. The scene cuts as Elaine and Frank lunge at each other, both with fists pulled back, at the ready.

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