Meaning – The term macroinstruction, refers to an instruction in a source language that is to be replaced by a defined sequence of instructions in the same source language and may also specify values for parameters in the replaced instructions.
It may also refer to an assembler language statement that causes the assembler to process a predefined set of statements called a macro definition. The statements normally produced from the macro definition replace the macroinstruction in the program.
The term macroinstruction may also be referred to as a macro, which is a rule or pattern that specifies how a certain input should be mapped to a replacement output. Applying a macro to input is macro expansion. The input and output may be a sequence of lexical tokens or characters or a syntax tree. Character macros are supported in software applications to make it easy to invoke common command sequences.
Example of usage – “Macros are used to make a sequence of computing instructions available to the programmer as a single program statement, making the programming task less tedious and less error-prone.”