Years ago I was bewildered by this question and now it has stumped me again. I did a little research for the correct answer. When I pick up my friend Jackie every Sunday we meander over about four speed “humps” and my question is why they are a “hump” and not a “bump.” “Speed bumps and speed humps are just different approaches to the same problem; slowing down vehicles. Speed humps tend to be slightly smaller in height than speed bumps but longer, whereas speed bumps are taller and more likely to be found in a parking lot.” Now I know – I am on a rural road and the humps aren’t too high and are there to just keep me at a slower speed. Now I know.
Tara Truly 