The time elapsed from the start to the end (one cycle) of an operation. It is the time taken to complete processing of a single unit of a product/transaction and includes the time consumed by all activities within the process area including product/service creation or transformation, wait time, transportation, and rework. Cycle time is a function of the number of things in the process area and the process exit rate (see “Little’s Law”).
For a cable company, the cycle starts when the application is received and ends when the customer gets a new cable connection. The duration of time between start and finish constitutes the cycle time for providing a cable connection.
A Case Study on Reducing Cycle Time: - http://www.isixsigma.com/library/content/c040419a.asp