1. A measure of computing speed; formally, ‘Million Instructions Per Second’ (that's 106 per second, not 220!); often rendered by hackers as ‘Meaningless Indication of Processor Speed’ or in other unflattering ways, such as ‘Meaningless Information Provided by Salesmen’. This joke expresses an attitude nearly universal among hackers about the value of most benchmark claims, said attitude being one of the great cultural divides between hackers and marketroids (see also BogoMIPS). The singular is sometimes ‘1 MIP’ even though this is clearly etymologically wrong. See also KIPS and GIPS.
2. Computers, especially large computers, considered abstractly as sources of computrons. “This is just a workstation; the heavy MIPS are hidden in the basement.”
3. The corporate name of a particular RISC-chip company, later acquired by SGI.
4. Acronym for ‘Meaningless Information per Second’ (a joke, prob.: from sense 1).