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premature acceleration 

When the person behind you in traffic changes lanes and accelerates to pass only to find that there is not enough room and they have to get back in line.
Driver: Did you see that guy try to pass me? He had to slow down and get back in line.
Passenger: Yeah, that was a case of premature acceleration.
premature acceleration by Morgore December 18, 2008

Accelerationism 

A political philosophy that maintains that a country's current government/society is broken beyond repair, and the only way to fix it is to force things to get even worse so as to completely collapse the system under its own weight and remake it.

Often related to "taking the black pill."
Joey believes in accelerationism because he hates the world he lives in so much that he figures utter chaos is better than what's currently ongoing.
Accelerationism by AOmundson September 22, 2020

acceleration 

Defined as the change in velocity over a period of time. Acceleration is a vector quantity and therefore is stated as a quantity with a direction.

a = (v-u)/t (where a, v and u are vectors)

Where (using SI units):
a = acceleration of the body in metres per second per second (ms^-2, or metres per second squared)
v = final velocity of the body in metres per second (ms^-1)
u = initial velocity of the body in metres per second (ms^-1)
t = time period between the initial and final velocity, in seconds (s)

An accelerating body can also be decelerating (ie, negative acceleration) or be at rest. Also, instantaneous acceleration is a bit different.
1) A car that is travelling at 2ms^-1 changes its speed to 6ms^-1 over a period of five seconds, and doesn't change direction. During that five seconds, it had an average acceleration of .8ms^-2 in initial direction.

2) A car travelling forwards at 2ms^-1 is suddenly put into reverse and five seconds later it is travelling 2ms^-2 backwards. It's average acceleration is .8ms^-2 backwards (-.8ms^-2 forwards). Note in this example, the car would have been temporarily at rest just when it changes direction. It is still accelerating (in negative direction, ie backwards, ie decelerating) during this period.
acceleration by White Razor December 24, 2008

Premature Acceleration 

When a automobile begins to accelerate before it is prudent. Most often witnessed at intersections that are controlled by traffic lights when a driver incorrectly assumes that it is his turn to go next.
Driver: Look at that guy raring to go. I'll bet he doesn't know that it's my turn to go next.

<Car in question moves about a foot and then stops abruptly as he realizes his light did not change green>

Passenger: How embarrassing; a classic case of premature acceleration.
Premature Acceleration by Mit Long February 12, 2010

Mass times Acceleration 

acceleration marks 

Acceleration marks are crap stains that you intentionally leave in your underwear. They are in essence, the opposite of skid marks, and are so named accordingly.
All that chilli I ate yesterday has let me do some sweet acceleration marks in my shorts. Just a little scratching is all it takes.
acceleration marks by the nesto December 23, 2007
More from Urban Dictionary
A dead drop is a location used to secretly pass items between two people, without requiring them to meet.

Spies have been known to use dead drops, using various techniques to hide the items and to signal that the drop has been made. Drug dealers use this as well.

A common place is to duct tape the item to the underside of a toilet cover in a public restroom.

A signal is sometimes used as well to indicate there is something to pickup, like a pile of stones in a certain formation. After checking the drop the signal is removed.
"The dead drop is the restroom toilet at the Gulf station at the corner of Commercial Ave. and Georges Rd."
dead drop by rubberroom July 23, 2008
Word of the Day on November 9, 2026

No Surprises Wedding

A "No Surprises Wedding," or NSW, is a wedding invitation designation that tells attendees that there can be no unplanned announcements, engagements, events or speeches at the wedding - all actions must be pre-approved by the couple. Anyone who performs an unapproved "surprise" will be asked to leave the wedding early.

This designation comes from Reddit, where so many stories of bad wedding behavior indicated a need to communicate expectations for the wedding behavior of attendees.
You are cordially invited to the nuptials of Brian and Tom on October 31 at noon.

Please note that this wedding is child-free (under 10) and a No Surprises Wedding (NSW). Reach out to wedding planner Sami Smith to request approvals or exceptions; please note that exceptions will be rare. Limited child care for under-10s will be available. All approvals will be noted and included in planning. Unapproved, or surprise exceptions, will result in guests being asked to leave.
Word of the Day on November 8, 2026
Ulzzang true definition is "best & "face" = best face in korean. They are basically people with above average looks, sometimes with the use of photoshop and haduri who post their pics online, some becoming internet celebrities.
"Hey, see that chick over there? She's pretty enough to be an ulzzang. :D"
ulzzang by `r i k kit t y February 26, 2008
Word of the Day on November 7, 2026
EBK stands for "Elite Ball Knowledge." 1 In internet slang, "ball knowledge" originally referred to a deep understanding of football/soccer or basketball, but it has evolved into a broader term for having a highly sophisticated, deep, or niche understanding of any specific topic (such as music, movies, or subcultures).
Person A: "That scene was a direct homage to an unreleased 1982 Japanese indie film."
Person B: "Wow, EBK."
EBK by silwhett November 5, 2026
Word of the Day on November 6, 2026
A seemingly endless debate with a idiot
I don't know man im not ready for yap trap stupidity today which always tries to suck you into it
Yap Trap by WolfieSnack November 4, 2026
Word of the Day on November 5, 2026
Texas is categorized as a swing state in presidential elections, but has voted for Republicans more times than for Democrats in recent history. As such, as demographics change political alignments, some Democrats believe that Texas will vote blue, or Democratic, due to their Hispanic and African American voters, who often align themselves with the Democratic Party's liberal wing.

Blexas has been cited as possible in the upcoming decades, but only if Democrats continue to win the Hispanic vote in bigger margins.
Democrat 1: What is your prediction for the 2024 presidential election?
Democrat 2: Well uh, Blexas!
Democrat 1: You've been saying that since 2008 though.
Blexas by Tritonist June 14, 2021
Word of the Day on November 4, 2026
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