What Does Microarchitecture (µarch) Mean?
Microarchitecture, abbreviated as µarch or uarch, is the fundamental design of a microprocessor. It includes the technologies used, resources and the methods by which the processor is physically designed in order to execute a specific instruction set (ISA or instruction set architecture). Simply put, it is the logical design of all electronic components and data paths present in the microprocessor, laid out in a specific way that it allows for optimal execution of instructions. In academe this is called computer organization.
Techopedia Explains Microarchitecture (µarch)
Microarchitecture is the logical representation of how a microprocessor is designed so that the interconnections between components – the control unit, the arithmetic logic unit, registers and others – interact in an optimized manner. This includes how buses, the data pathways between components, are laid out to dictate the shortest paths and proper connections. In modern microprocessors there are often several layers to deal with complexity. The basic idea is to lay out a circuit that could execute commands and operations that are defined in an instruction set.