In Avengers: Endgame (2019), Tony Stark says about Thanos:
Tony Stark: I didn't fight him. No, he wiped my face with a planet... while the Bleecker Street magician gave away the store.
What is the meaning of "wiped my face with a planet"?
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Sign up to join this communityIn Avengers: Endgame (2019), Tony Stark says about Thanos:
Tony Stark: I didn't fight him. No, he wiped my face with a planet... while the Bleecker Street magician gave away the store.
What is the meaning of "wiped my face with a planet"?
"...wiped my face with a planet" means exactly what it says, from when Thanos brought a planet (actually one of Titan's moons1) down on Tony during their battle in Avengers: Infinity War.
As mentioned by @systemexit in a comment below it could also be a play on the American idiom cleaned one's clock meaning "to trounce one’s opponents". Thanos won (even if largely because of Star-Lord and Strange), he then proceeded to Snap and so did trounce them.
To "give away the store" is an expression that means to have traded/negotiated poorly. He says this because Strange gave up the Time Stone to Thanos in exchange for Tony’s life in Avengers: Infinity War something he said he would never do.
Doctor Strange: Alright, Stark. We go to him. But you have to understand... if it comes to saving you or the kid or the Time Stone... I will not hesitate to let either of you die. I can't, because the fate of the universe depends on it.
[...]
Doctor Strange: Stop! Spare his life... and I will give you the stone.
Thanos: No tricks.
Tony Stark: Don't...!
1It's not too relevant but to clear it up from the comments, yes this specific Titan in the MCU is a planet. The object Thanos brings down is one of Titan's moons.
Normally, you wipe your face with a towel or a napkin. Also, you normally wipe your own face, unless you are a child. Tony is emphasizing that this "fight" was not a fight at all. Thanos treated him like a child by wiping his face and was powerful enough that he did it with a planet (moon, technically) instead of a towel
It can also be a frame challenge. If we are talking about the area in general, Tony was hit so hard his face slid along the ground. If we are talking about a Tony focused concept where he is the center, the planet moved and he was still. Therefore the planet was wiped across his face by Thanos who had the power to move planets. "if the mountain won't come to Muhammad, then Muhammad must go to the mountain" The line works in more ways than one. Such is the hallmark of good writing. @thelethalcarrot was right about the store.