鷄鳴狗盜(계명구도)

닭이 울고, 개가 훔치다.
닭처럼 울고, 개처럼 훔치다.
비열하게 다른 사람을 속이는 하찮은 재주를 가리킨다.
천한 재주로 다른 사람을 속이는 사람을 비유적으로 이르는 표현이다.
하찮은 재주라도 경우에 따라서는 어딘가에 쓸모가 있다는 의미로도 쓴다.
제(薺)나라 맹상군(孟嘗君)이 진(秦)나라 소왕(昭王)에게 잡혀 옥에 갇힌 때에 개의 흉내를 잘 내는 식객이 개처럼 몰래 궁중의 창고로 숨어 들어가 맹상군이 이미 소왕에게 준 호백구(여우의 흰 겨드랑이 털로 만든 옷)를 훔쳐 소왕의 후궁에게 바치고 옥에서 빠져나오고, 도성을 빠져나가려 할 때에 이른 새벽이라 아직 성문이 열리지 않아 닭의 울음소리를 잘 흉내내는 식객이 닭의 울음소리를 내자 수문장이 성문을 열어 제나라로 무사히 돌아온  고사에서 유래한다.

chicken crows, dog steals
cock cry, sneak thief
crow like a chicken and steal like a dog
From the story of Lord Mengchang(孟嘗君) escaping from King Zhao of Qin(秦昭王) with the help of his two retainers, one crowing like a chicken and the other disguising as a dog to sneak into the Qin palace to steal a white fur coat for the king's concubine.
a person, especially of a small caliber, who is only capable of petty tricks
lowly skills
skills of little worth
people with lowly skills
base and despicable
 
《史記 孟嘗君傳》 此時孟嘗君有一狐白裘，直千金，天下無雙，入秦獻之昭王，更無他裘。孟嘗君患之，遍問客，莫能對。最下坐有能為狗盜者，曰"臣能得狐白裘"。乃夜為狗，以入秦宮臧中，取所獻狐白裘至，以獻秦王幸姬。幸姬為言昭王，昭王釋孟嘗君。孟嘗君得出，即馳去，更封傳，變名姓以出關。夜半至函谷關。秦昭王後悔出孟嘗君，求之已去，即使人馳傳逐之。孟嘗君至關，關法，雞鳴而出客，孟嘗君恐追至。客之居下坐者有能為雞鳴，而雞齊鳴，遂發傳出。
《사기 맹상군전》 차시맹상군유일호백구，직천금，천하무쌍，입진헌지소왕，경무타구。맹상군환지，편문객，막능대。최하좌유능위구도자，왈"신능득호백구"。내야위구，이입진궁장중，취소헌호백구지，이헌진왕행희。행희위언소왕，소왕석맹상군。맹상군득출，즉치거，경봉전，변명성이출관。야반지함곡관。진소왕후회출맹상군，구지이거，즉사인치전축지。맹상군지관，관법，계명이출객，맹상군공추지。객지거하좌자유능위계명，이계제명，수발전출。
At this time, Lord Mengchang once had an expensive and unique white fox-fur coat, and as he entered Qin, he offered it to king Zhao, who wanted no other fur. Mengchang was worried and asked his followers, but none could come up with a solution. The lowest-ranked of them, who could steal like a dog, says that he could get the fur coat back. That night, the thief disguised as a dog, entered the Qin royal treasury, stole the fur coat, and offered it to the king's favourite lady, who was able to persuade King Zhao to release Mengchang. Once he was released, Mengchang departed immediately, changed his identity, and faked his credentials in order to exit the frontier pass. At midnight, they reached the Hangu Pass. King Zhao of Qin regretted releasing Mengchang and attempted to find him, but he had escaped already. Thus, the King ordered his men to chase him on fast postal horses. Mengchang reached the Hangu Pass. By law, travellers were not allowed to exit the pass until morning when cocks cry. Mengchang was afraid that the soldiers would get him. One of his followers could imitate the cry like a cock. When he starts to cry, the cocks nearby all started to cry one after another. Then, Mengchang presented his fake credentials and exited the Hangu Pass.