Wiktionary
a. Not spring.
Usage examples of "unsprung".
Grandma a constant, a clock, a pendulum, a face to tell all time by at noon, or in the middle of sick nights when, raved with fever, we saw her forever by our beds, never gone, never away, always waiting, always speaking kind words, her cool hand icing our hot brows, the tappet of her uplifted forefinger unsprung to let a twine of cold mountain water touch our flannel tongues.
Something large and solid had brushed by my leg, and although there are a lot of large and solid things in the sea all I could think of was of something about fifteen feet long with a triangular fin and a mouth like an unsprung bear-trap.
The grass covering had been torn away from the head by careless handling and long months of travel on the shoulders of porters and on the buckboards of an unsprung Cape cart.