critical mass

critical mass
—n
1.	the minimum mass of fissionable material that can sustain a nuclear chain reaction
2.	the minimum amount of money or number of people required to start or sustain an operation, business, process, etc: the critical mass for a subscription digital sports channel

critical mass   The smallest mass of a fissionable material that will sustain a nuclear chain reaction. The amount of matter needed to generate sufficient gravitational force to halt the current expansion of the universe. See also big bang, big crunch.

critical mass definition

In physics, the amount of material that must be present before a chain reaction can sustain itself.

Note: The term critical mass is used to refer generally to the minimum amount of something needed to produce a given effect: “The town needs a critical mass of industry to attract more business.”

critical mass definition

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.
[Jargon File]
(1994-12-23)