1. Favored term to describe programs or hardware that seem to eat far more than their share of a system's resources, esp. those which noticeably degrade interactive response. Not used of programs that are simply extremely large or complex or that are merely painfully slow themselves. More often than not encountered in qualified forms, e.g., memory hog, core hog, hog the processor, hog the disk. “A controller that never gives up the I/O bus gets killed after the bus-hog timer expires.”
2. Also said of people who use more than their fair share of resources (particularly disk, where it seems that 10% of the people use 90% of the disk, no matter how big the disk is or how many people use it). Of course, once disk hogs fill up one filesystem, they typically find some other new one to infect, claiming to the sysadmin that they have an important new project to complete.