It's supposed to reflect transistor density. If you take a chip made on a say 90nm process and shrink it by 90x it should have approximately the same transistor

It's supposed to reflect transistor density. If you take a chip made on a say 90nm process and shrink it by 90x it should have approximately the same transistor density as a "marketing 1nm" chip. The scaling stopped around 45 nanometers. You can see this if you compare 2 processes: Intel 45nm had 2,779,468 transistors/mm², and the Apple A14 (7nm) had a transistor density of 134,100,000 t/mm² 2,779,468*(45/7)²=114,865,769, so the two are quite close. https://en.wikipedia.org/wiki/Transistor_count#Microprocessors https://en.wikipedia.org/wiki/Transistor_count#Microprocesso...