The Free On-line Dictionary of Computing (30 December 2018):

software life-cycle
life-cycle

    The phases a software product goes through
   between when it is conceived and when it is no longer
   available for use.  The software life-cycle typically includes
   the following: requirements analysis, design,
   construction, testing (validation), installation, operation,
   maintenance, and retirement.

   The development process tends to run iteratively through these
   phases rather than linearly; several models (spiral, waterfall
   etc.) have been proposed to describe this process.

   Other processes associated with a software product are:
   quality assurance, marketing, sales and support.

   (1996-12-27)