"qdf" stands for "queer dick fucker", but can also refer to the highest form of online simp, someone who would even go so far as to buy a girl Minecraft cosmetics or send them shower nudes without dating.
Evan: Want to have sex?
Taylor nah im not a qdf

Evan: damn Chelsea is looking sexy, might buy her a Hypixel rank
Taylor: Stop being a qdf lmaoo
by TaylorThePenguin November 26, 2020
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Qdf is the same as saying wdf or wtf, but it is much much cooler.
It might also be a spelling mistake... meh.
QDF!!! My sister threw up on my books!
Qdf dude, you stole my kill.
by Matt-Not_Taken_Anymore May 21, 2008
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Security for the Roblox game "QSERF". Mostly comprised of military-obsessed 14-year-olds.
Let's go annoy that QDF guard over there.
by notatrampoline April 2, 2021
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Stands for || Quantum Defense Firm ||, a branch of the "Quantum Science Inc." responsible for the enforcement of defense, safety and order within their facilities, and other tasks that require their combat capabilities.

|| NOTE: Taken from the QCOD - "Operatives within QDF are highly trained militarized soldiers tasked with defending facilities under the umbrella of the Quantum Corporation and other contracted facilities, companies, assets, political figures, intelligence gathering firms, and so forth."

|| Due to their passion at maintaining order and sticking true to their duty, they are often mocked by pricks for being "too serious in a kids' game".
1. "Oh hey, looks like a QDF is up for patrol right now. We should be responsible, law-abiding civilians and employees to avoid being pricks who disrupt their duty so we don't get shot or beat up like training dummies"

2. "Oh man, that's a lot of QDF today, there's no chance for us to prime the warhead. I say we just stick to Deathmatches for now until we gain enough numbers, or wait for some of them sign off..."
by Alch3mIx September 18, 2021
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Someone who despises the group Quantum Defense Firm most likely because they were shot to death once accidentally by a Firm member
Guy 1: QDF is bad!!11!
Guy 2: Shut the fuck up QDF hater
by ahandlethatisnotinuse August 7, 2021
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