If you're annoyed or angry with whoever you're talking to it basically means whatever, just get the hell out of your face, shuttup, and leave you the fuck alone.
If you're not mad it means: Ok, sure I'll go along with that; or I'll do it later.
Can also be used with affection to a loved family member in place of "I love you too," in some cases.
Ex. 1
Teen: (goes downstairs to get a snack and drink)
Grandmother: (limps in with cane) It's your day to clean the kitchen
Teen: (in an indifferent tone) If you say so (goes upstairs with snack and drink and continues to play on computer)
Teen: (thinking to self) I can't stand that bitch, she gets on my fuckin' nerves! She needs to turn on the damn air conditioning cuz it feels like a sauna up in dis bitch!
Grandmother: (downstairs in kitchen)(limping slowly with cane to get a drink)

Ex. 2
(daughter and father finishing a phone conversation)
Daughter: What are we doing when you get off work?
Father: I don't know sweetheart, probably nothing (obviously kidding). I have to go now, I have a customer that I need to get back to. I love you.
Daughter: Daad come on!
Father: I have to go now, I'll call you back later. Bye, I love you, and I'll see you when I get home.
Daughter: If you say so, bye! (hangs up phone and continues to watch TV)
by Qu33n0fH3@rt$ July 20, 2008
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the part in 𝙞𝙢 𝙛𝙞𝙣𝙚 by 𝘽𝙏𝙎 that sends me to mars. That shit go harder than yo daddy. And I oop-
Nicole: HeY man how ya doing
Marty: ....
Marty: “IM SO FINE YOU SO FINE” *mic drop*
by It’syahomeboiyoongi June 18, 2019
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the line mario says at the end of super Mario 64
player: alright! i just beat super mario 64!

mario from the end screen: thank you so much for to playing my game

player: what
by mariofeds December 29, 2022
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It means that, he/she misses you and wants you next to them. IN PERSON Also, it means he/she loves you.
i want you so bad like literally
by xtra_ordinary_queen_zia January 18, 2017
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The perfect phrase to let someone know how much you love them... especially for the competitive, yet romantic couple.
guy says, "i love you." girl says, "well, I love you so much its retarded."
by naanaalovessangriaaa February 11, 2010
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A song written sang by Lea Michele, which is in her debut album, Louder. “If You Say So” is about Michele’s late boyfriend, Cory Monteith. Her song is about having trouble coping with Monteith’s death. Michele says in her song, “You said, I love you girl/ I said, I love you more/ Then a breath, a pause, you said/ If you say so,” which is their last conversation they had.
Lea Michele’s song, If You Say So, is so sad.

I cried listening to If You Say So.

Oh my god Rebecca! Don’t play If You Say So I’m going to cry!
by Lea Sarfati February 1, 2019
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Aldo, urban dictionary, your merch is {look at the gif}
by Qwertyuiopasdfghjkllkjhgfdsapo December 17, 2020
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