In physics, the minimum amount of fissionable material required to sustain a chain reaction. Of a software product, describes a condition of the software such that fixing one bug introduces one plus {epsilon} bugs. (This malady has many causes: {creeping featurism}, ports to too many disparate environments, poor initial design, etc.) When software achieves critical mass, it can never be fixed; it can only be discarded and rewritten.
[glossary]
[Reference(s) to this entry by made by: {hacked up}{rococo}]