Hi, now we have the term "bump". It's very easy to remember what it means. We are paying attention to two of its meanings:
First meaning: observe this picture and tell what the kid has on his head.
Well, that's a bump, a head bump. It must have been painful.
Second meaning: observe the picture below, the tyre is just on the bump.
And this is a speed bump. Easy to remember, right?
Actually the meaning is the same in the two cases: "a round, raised area on a surface or on the body"