something that works very smoothly and effectively:
The office runs like a well-oiled machine.
WORD CHOICE: WORD CHOICE: machine, device, gadget, applianceA machine is a piece of equipment that uses power to do a particular job. It is usually large and stays in the same place• a machine that sorts mail • a washing machineYou use the words device and gadget especially when you think the equipment is very cleverly designed. A device is a piece of equipment that does a particular job, for example takes measurements or controls the operation of a machine. It may use electrical power or be used by hand• a device for detecting blood alcohol levels from breath samples • a temperature control deviceA gadget is a small piece of equipment that does something useful or impressive• one of those gadgets that sorts coins • kitchen gadgetsAn appliance is a piece of electrical equipment used in your home such as a washing machine or fridge. This word is used especially by the companies that produce and sell them• the world's largest producer of household appliances • domestic appliances
Definition of machine from the Longman Dictionary of Contemporary English within the topic GROUPINGS