What is "quavery"

Usage examples of "quavery".

His voice was frail, almost quavery, yet it filled the small church, quietening the crowd more successfully than any threats from the guards.

Best of all, Mami seemed not to mind the singing anymore and once or twice broke out into song herself in a delicate, quavery soprano: A Santa Clous le gusta el vino, A Santa Claus le gusta el ion.

The fear-crazed neural message would race down the full length of the motor neuron in his extended arm (vaulting synapse junctions), and in time, always in the nick of time, the quavery hand would be jerked back.

Many nights, I've heard the eerie, quavery yawling of coyote packs chasing prey and celebrating slaughter.