Their muscles become stiff. They might bump into things or fall over objects.

VOA: special.2009.12.30

And then something went BUMP! How that bump made us jump!

VOA: special.2010.05.02

"I've known other actresses who had it." "I had a friend who had a little bump on her nose.

VOA: standard.2010.07.22

"We're probably,it looks now, like we'll continue to bump along maybe even have some bad months and unemployment is not going to recover as it has in some past recessions."

VOA: standard.2010.01.15

"There's been a bump in the road here, but it will be good to get back to the talks there will be good days and bad days, as there always are in these sorts of negotiations.

VOA: standard.2009.09.05