Copasetic
adj: completely satisfactory; "his smile said that everything was copasetic"; "You had to be a good judge of what a man was like, and the English was copasetic"- John O'Hara .

The word COPESETIC originated in Chicago during Prohibition. One of the major hotels downtown was notorious as being a meeting point for various nefarious activities. Whiskey and gin were sold out of various rooms, prostitutes could be had for a pittance, gambling took place on the premises. The situation became so bad that even the corrupt Chicago political machine became embarrassed, so they finally posted a full-time policeman in the lobby to keep an eye on activities. This did have the desired effect as many former customers were wanted by the police and with this cop on duty, they did not dare to show their faces in the lobby. However, human nature being what it is, the desire for the goods and services was still present, so the underworld posted their own lookout to keep an eye on the policeman. During the wee hours of the morning, with little going on, the policeman would frequently rest his aching feet by sitting down and resting on a sofa (known as a settee at that time) which was positioned in a prominent position so that he could observe the going's and coming's of the hotel clientele. Frequently, he would drop off to sleep. In this case, persons arriving at the hotel would go up to the lookout to find out whether or not it was safe for them to enter the hotel. If the lookout replied, "The Cop is on the Settee," it meant that he was sound asleep and it was safe to enter the building. The phrase was used so much that it eventually was shortened to the version we know today as COPESETIC, ............say it real fast............THECOPISONTHESETTEE. (来源：英语麦当劳www.EnglishCN.com)