Definition - What does Disassembler mean?
A disassembler is software that converts machine language instructions into assembly language instructions (also known as reverse engineering). As the term implies, a disassembler performs operations that are the inverse of operations performed by an assembler.
Techopedia explains Disassembler
A disassembler is used to translate machine code into a human readable format. Reading disassembled code is more complex than original source code because disassembled code lacks programmer comments and annotations.
A major disassembling issue is differentiating code and data, which are shown in the same way in current machines.