Definitions for "Hot Swappable"
A device that can be installed on the computer without rebooting the system e.g. USB devices.
Component that can be plugged into a PC while it is running. The PC registers the device and configures it without rebooting.
Components that can be removed and replaced while the switch is in operation.
A part that can be removed from a computer safely without turning the power off. Examples are Redundant Power Supplies and disk drives.
Battery: A feature that allows an uninterruptible power supply (UPS) battery to be changed for maintenance without taking the UPS and the equipment connected to it, off-line.
Keywords:  critical, module, load, ability, taking
The ability to change a module without taking the critical load off the UPS.