Other forms: jumpier; jumpily; jumpiest
Someone who's jumpy is anxious and jittery. If you've ever been so nervous that you couldn't sit still, you know how it feels to be jumpy.
This informal adjective is perfect for describing the sort of anxiety you can't hide. If you're shifting in your seat, crossing and uncrossing your legs, and nervously tapping your fingers on your knees as you wait to give a speech, you're jumpy. Jumpy also means "bumpy," as when you take a jumpy bike ride along a rocky, unpaved road.