a guardian or defender against theft or illegal practices or waste
a dog trained to guard property
同义词：guard dog
watchdog详细解释
watch.dog
n.（名词） A dog trained to guard people or property. 看家狗：训练用来保护人或财物的狗 One who serves as a guardian or protector against waste, loss, or illegal practices. 监察者：防止浪费、丢失或不法行为的监察或防护者
