I have a related problem. Of course they've never heard of "Arduino." So then I say "Like a BASIC Stamp, right?" And they've never heard of those, either. So then what do I call it?
Seems to me this whole activity is where imbedded processing and physical computing meet. "Micro-controller" might be technically accurate but it doesn't seem to communicate anything to the casual enquirer.
So what DO I tell someone who looks at my prototype board and says "What is that?"
See "verbose"