Americans; I am trying to understand the subtlety and nuance of your expression “to haul ass”.
Does it mean “to hurry”? Or more “to move under strain”?
Or something else?
You should also try to understand how this instance works including the rules.
What?
It seems like others have already given the definition, but I do want to introduce you to the wonderful thing that is Wiktionary.

https://en.wiktionary.org/wiki/haul_ass
It’s part of the same project as Wikipedia, and it has a very comprehensive compendium of definitions for slang terms.
Urban Dictionary is also great for slang definitions
https://www.urbandictionary.com/define.php?term=haul ass
And you can use a DuckDuckGo bang as a shortcut:
!ud haul assAwesome, I didn’t know it know had slang 👍
In my opinion Wiktionary is probably the best English dictionary on the planet and probably the best English to other language dictionary as well.
Urban dictionary for academics
Urban Dictionary for people who actually want to know what words mean
It means ‘to be putting lots of effort into moving fast’. Often with a connotation of doing so to an irresponsible extreme.
It means to move with all possible haste.
I thought it was similar to the phrase “quick, fast, and in a hurry” or “I need this done by yesterday”
Like it’s a call to action to save your ass
It’s an urgent “hurry” maybe similar to “careening”
TIL!
Careening specifically implies having little control while going fast. Hauling ass doesn’t suggest lack of control.
Funniest thing I ever heard my father say when I was a kid was when we were at a stop light waiting for an overweight man to finish crossing the road: “If that guy ever wanted to haul ass he’d have to make two trips.”
Obviously not something I would perpetuate or use as a considerate grown up, but provided maybe to lend some American context around the phrase.
To me it means to move quickly. Often it means to move quickly under strain, but not necessarily.
(Moving slowly under strain is not hauling ass.)
The best example I can think of would be the insane running animations of Peppino from Pizza Tower:


And this scene from Rat Race (2001) is maybe less helpful but still relevant: https://youtu.be/PzjLImF8Zbc?t=1m5s
To hurry or leave.
But my mental picture is a donkey in a trailer…
Bear with me
Tell the bear I said hello.
Some additional nuance that I didn’t see yet: there’s a specific meaning to the command or the future tense of hauling ass, as that usage tends to imply the need for haste, specifically to hurry, e.g., “we gotta haul ass”. However, in the past or subjunctive tense, it tends to mean great speed without necessarily implying anxiety or haste - the speed could be entirely innate and casual - e.g., “they were really hauling ass” or “this thing can really haul ass”.
In my mind, hauling ass means to go as fast as possible, generally dangerously so. There usually is a solid reason for it, like escaping something, making it somewhere on time when you’re already late. I’d say it’s under strain, but the strain isn’t that you’re carrying a load, it’s that you’re pushing your vehicle or yourself to its limits, or perhaps beyond them.
It means all of the above, but the typical usage is to go really fast.
I have used that saying to mean time to leave.
It means to move fast or with urgency depending on who says it and what context
Go fast or hurry up.
Going fast.









