Space Shuttle Debris

DebrisI had my kids watch the space shuttle takeoff today.  It was fun for them.  Then later the news started to talk about "debris" spotted on shuttle video during the launch.

All day something rubbed me the wrong way, and I'm not sure if I'm right on this or not.  But is "debris" the right word for spotting something falling off the shuttle or fuel tank or whatever?  I looked it up in and Merriam-Webster and neither gave a definition of "debris" that seemed to fit the context.  At best it's a piece of something that's been destroyed, not something that has one piece fall off.  Thoughts?