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negative mass

A form of mass that repels, not attracts.
Expressed as: -1 kg
Guy 1: I'll put negative mass in my friend's bed so he can't sleep.
- later -
Guy 2: WHY CAN'T I GET IN MY BED?!?!?!?
Words you can keep

Negative Mass and Anti-Mass

Hypothetical forms of matter that would respond to forces in reverse—push them, and they accelerate toward you; pull them, and they accelerate away. Negative mass would violate everything we know about physics while enabling reactionless drives, warp bubbles, and perpetual motion machines. Anti-mass is even stranger, potentially canceling out normal mass and creating all sorts of paradoxical effects. Neither has ever been observed, and most physicists suspect they're impossible. But the math allows them, and where math leads, dreamers follow. Negative mass and anti-mass are the ultimate engineering fantasy: materials that would let you build starships, time machines, and devices that make your commute actually enjoyable. They're also the ultimate scientific cautionary tale: just because you can write an equation doesn't mean you can build a thing.
Negative Mass and Anti-Mass Example: "He claimed to have synthesized negative mass in his garage, proving it with a video of something moving the wrong way when pushed. The video was blurry, the methodology was absent, and the object looked suspiciously like a balloon on a string. Negative mass remained in the realm of theory, where it could be as wonderful as imagination allowed."

Theory of Negative Mass

A speculative framework proposing the existence of mass with negative value—objects that would accelerate away from force, fall upward in gravity, and exhibit other counterintuitive behaviors. Unlike anti-mass (which might be a distinct property), negative mass is simply mass with a minus sign in the equations. Negative mass would be repelled by positive mass, creating bizarre dynamics: push it away, and it accelerates toward you; pull it toward you, and it accelerates away. The theory has been explored in general relativity, where negative mass could theoretically enable wormholes and warp drives. No negative mass has ever been observed, but the equations allow it—and where equations allow, imagination follows.
Theory of Negative Mass "Push a negative mass object away, and it accelerates toward you. Pull it toward you, and it flees. Negative Mass theory says this isn't magic; it's just physics with a minus sign. The Alcubierre drive might require negative mass to work. We've never seen it, but the math doesn't forbid it. Sometimes that's enough."
More from Urban Dictionary
(Ewokese) Freedom!
And dying in yo' bed many years from now, would ya be willing ta trade all da days from dis here day ta dat fo' one chance, just one chance, ta come back here as young men an' tell our enemies dat dey may take our lives but dey will never take our freedom ... YUB NUB!
yub nub by rotjrem November 4, 2010
Word of the Day on September 4, 2026
1. Meaning nasty, sexy, filthy. Popularized by Christina Aguilera.

2. Used usally as a close friend in hip-hop slang.
1. Wanna get dirrty
It's about time that I came to start the party Sweat drippin' over my body
Dancin' gettin' just a little naughty

2. Sup Dirrty? Haven't seen you in a while.
dirrty by Minty November 30, 2003
Word of the Day on September 3, 2026

Coyote Ugly

1. Place

The Bar came before the movie. It is an awesome bar where the girls know how to party and make you feel okay about giving up your money, drawers, bras, and dignity.

2. Movie

A story about a Jersey girl following her dreams, aided by working at this bar in New York.

3. Situation/Person/Decision

See other definitions - waking up next to someone so ugly you'd rather chew your arm off than wake them up.
1. Yo, Coyote Ugly is my favorite bar! I got whipped, stripped, drunk, and danced on the bar all before 7 o'clock!

2. Hey did you see Coyote Ugly? It actually has a plot!

3. Ugg I woke up to Coyote Ugly this morning!
Coyote Ugly by jerseycountry March 8, 2009
Word of the Day on September 2, 2026

Literally 1984 

Used in response for when someone promotes/advocates an event or idea that is perceived to support "too much" authority and/or government control.

Often used jokingly as a over-exaggeration in political talk.

Can also be used in response to a ban or mute in a forum site or online chat.
Steve: I think that the government should regulate businesses more
Bob: Literally 1984!

--User1 has been permantly banned--
User2: You cant ban my friend like that! Literally 1984!
Literally 1984 by ke1 July 7, 2021
Word of the Day on September 1, 2026

Back when I lived in upstate new york 

A meaningless, unimpressive, self-serving introduction. An indicator that the story about to be shared will be pointless and dumb.
Back when I lived in upstate new york, I also had to park on the street - on two occasions, we got enough snow, mixed with just the right plowing, that my car was lifted off the ground from so much snow being jammed underneath it.
Word of the Day on August 31, 2026
Acronym, meaning Too Long Didn't Understand
Similar to TLDR
Sister: This meeting was to discuss the rough draft of my essay, where we discussed the subsidiary questions I added in my rough draft. We also discussed the relationship between my main title and the real-life situations I chose to use in my essay. We discussed the structure of my essay as well, specifically the Math AOK section and how it relates to the contradiction of the title. This second meeting was particularly helpful in discussing the implications of my essay claims and how to apply the title across various areas of knowledge. There were many sections of the essay that could have been cut down in wordiness and the ways of knowing required further and more in-depth analysis.

Me: Woah! TLDU!
TLDU by L-Evans January 14, 2019
Word of the Day on August 30, 2026
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