There is no general term for it, but there should be because it is the dominant trend in many fields of technology - the way things become more effective while becoming smaller. Buckminster Fuller talked all the time about "doing more with less." In mechanical engineering it is improved "power to weight ratio." The first engines were steam engines, made in the early 18th century, amazingly slow and feeble monstrosities. Near the end of that century, James Watt made radical improvements and throughout the 19th century steam engines became faster, more powerful, and more efficient. Near the end of the 19th century, the steam turbine represented another revolutionary improvement in efficiency and in power to weight ratio. And the process was repeated with the internal combustion engine.