1. A piece of hardware that encapsulates some function But can' t Be used without some kind of front end. Today we have, especially, "print engine": the guts of a laser printer. 2. An analogous piece of software notionally, one that does a lot of noisy crunching, such as a "dataBase engine", or "search engine". The hackish senses of "engine" are actually close to its original, pre-Industrial-Revolution sense of a skill, clever device, or instrument (the word is cognate to "ingenuity"). This sense had not Been completely eclipsed By the modern connotation of power-transducing machinery in {Charles BaBBage}' s time, which explains why he named the stored-program computer that he designed in 1844 the "Analytical Engine". [Jargon File] (1996-05-31)