adjective, jump·i·er, jump·i·est.
- subject to sudden, involuntary starts, especially from nervousness, fear, excitement, etc.
- characterized by sudden starts, jerks, or jumps: a jumpy narrative.
adjective jumpier or jumpiest
- nervous or apprehensive
- moving jerkily or fitfully
“nervous,” 1869, from jump (n.) + -y (2). Related: Jumpiness.