The term comes from the race between two rats to get the piece of cheese at the other of the room first by trying to outrun each other. In the process, they spend more energy than the reward is worth. It signifies an endless, futile pursuit, a mad competition one embarks on. In real life situations, trying to outsmart colleagues to get a promotion before them by hook or crook represents a very common rat race. -Dr V Subramanyan, Mumbai