Answer: shuddering

AnswerCrossword Clue
shuddering(of a person) Tremble convulsively, typically as a result of fear or repugnance
shuddering(of a person's breathing) Be unsteady, esp. as a result of emotional disturbance
shudderingSHUDDER, to shiver or tremble
shuddering(esp. of a vehicle, machine, or building) Shake or vibrate deeply