Network partition

A network partition refers to the failure of a network device that causes a network to be split.

For example, in a network with multiple subnets where nodes A and B are located in one subnet and nodes C and D are in another, a partition occurs if the switch between the two subnets fails. In that case nodes A and B can no longer communicate with nodes C and D.

Also it can also be explained in a manner that if suppose a system is partition tolerant it means that even after a system is partitioned into multiple sub-systems it should work exactly in the same fashion as if in a single system.