Speed bumps are sometimes called “inverted potholes.” ” Does that refer to the inverted pot holes, otherwise know as speed humps?” was posted on the newsgroup aus.transport on March 13, 1999. “Humps are inverted potholes” was posted in The Guardian on March 25, 2008.
 
“Speed bumps are just expensive inverted pot holes” was posted on Reddit—Shower Thoughts on October 18, 2017.
   
           
Wikipedia: Speed bump
Speed bumps (or speed breakers) are the common name for a family of traffic calming devices that use vertical deflection to slow motor-vehicle traffic in order to improve safety conditions. Variations include the speed hump, speed cushion, and speed table.
 
The use of vertical deflection devices is widespread around the world, and they are most commonly found to enforce a low speed limit, under 40 km/h (25 mph) or lower.
 
Google Groups: aus.transport
Dim Jim Soorley claims credit for 50km/h limit - Is he crazy!?
Seppo Renfors
3/13/99
(...)
What the hell is “traffic calming”? Does that refer to the inverted pot holes, otherwise know as speed humps?
   
The Guardian (London, UK)
They give us the hump
Harry Phibbs
Tuesday 25 March 2008 05.30 EDT
Recent figures show that road humps may be doing more harm than good. The next mayor of London should have the good sense to flatten them
(...)
Humps are inverted potholes and as such a daily source of irritation to motorists.
 
Twitter
potholes.co.uk‏
@potholesuk
Speed humps are just inverted potholes, purposely built into the road. Here’s a site against them. http://www.joincrash.com
7:55 AM - 16 Mar 2010
 
Twitter
Dustin Treinen‏
@SilverBlizzard
Follow Follow @SilverBlizzard
@gabek those aren’t speed bumps, they are inverted potholes. some call them “outties”
3:15 PM - 5 May 2010
   
Twitter
Mkenya Daima‏
@japho1
A bump is an inverted pothole!
11:22 PM - 20 Jul 2011
 
Twitter
Padstersdad‏
@padstersdad
Follow Follow @padstersdad
@VictoriaCoren speed bumps are of course merely inverted potholes
2:17 PM - 24 Dec 2011
 
Twitter
Douglas Reid‏
@douglasreid
Speedbumps are sort of like inverted potholes. #idea
11:57 AM - 14 Feb 2012
 
Reddit—Shower Thoughts
Speed Bumps are just expensive inverted pot holes.
submitted October 18, 2017 by Combatxlemming
They are everywhere and make you slow down and sometimes you don’t see them.
 
Twitter
Shower Thoughts‏
@atshower
Speed Bumps are just expensive inverted pot holes.
8:09 AM - 18 Oct 2017