I would love to be able to provide a standard definition of programme management, unfortunately a commonly accepted definition does not exist.
If you open up Google and drop “definition of programme management” it returns over 3,000 results. Many of these are fairly useless but research a little further, through countless online sources, and you will come up with a feel for what programme management is. The problem is that there are many definitions, similar in some aspects but different in others.
Wikipedia offers “Program management or programme management is the process of managing several related projects, often with the intention of improving an organization’s performance”
The Association for Project Management (APM) offers “Programme management is the co-ordinated management of related projects, which may include related business-as-usual activities that together achieve a beneficial change of a strategic nature for an organisation. What constitutes a programme will vary across industries and business sectors but there are core programme management processes”
A nice succinct definition that came from the book “Program Management for Improved Business Results” and states “Program management is the coordinated management of interdependent projects over a finite period of time to achieve a set of business goals”.
This is probably enough to give one a flavour of what programme management is rather than a definitive answer.