Wiktionary
treadless
a. Without treads.
Usage examples of "treadless".
The tires are entirely treadless, as smooth and blank as the surface of a freshly washed blackboard.
Many of the trucks had treadless tires, so that they left no distinctive track in the sand.
A sprawling dump at one side of the big barn seemed to consist of a brass bedstead, half a tractor, a bottomless tin bath, the bones of an old wagon, a tangled heap of unidentifiable rusting metal, and roughly fifty treadless tyres of varying sizes.