High-overheadbaroquecode-intensivefeatureful, but costly.Especially used of communication protocols, language designs, and any sort of implementation in which maximum generality and/or ease of implementation has been pushed at the expense of mundane considerations such as speed, memory use and startup time.Emacs is a heavyweight editorX is an *extremely* heavyweight window system.This term isn' t pejorative, but one hacker' s heavyweight is another' s elephantine and a third' s monstrosity.Opposite: "lightweight".Usage: now borders on technical especially in the compound "heavyweight process".(1994-12-22)