Sentence:  When Timothy and Julia hurried up the staircase to the bedroom floor, where a considerable commotion was taking place, Tim took Barry Leach with him. .... The captive made no resistance and came not only quietly but in a series of eager little <WSD>rushes</WSD> like a timid dog on a choke chain. 
Meaning of the word marked with <WSD> tags:  A sudden forward motion.