The name stands for British Age Group Category and is a way of measuring and comparing the performance of swimmers across a range of different events and age groups.
The intention of the ASA is to encourage younger swimmers to compete in a wide range of events and not specialise in a particular stroke and distance too early. When a swimmer competes in a BAGCAT event their time is converted into points that take into account not only their time but also the stroke, their age, sex and various correction factors.
Please read the ASA Technical Swimming Committee statement on BAGCAT point scoring from 2010 for more information.