referred to "a constructor of military engines". In this context, now obsolete, an "engine" referred to a military machine, i.e., a mechanical contraption used in war (for example, a catapult). Notable examples of the obsolete usage which have survived to the present day are military engineering corps, e.g., the U.S. Army Corps of Engineers.

The word "engine" itself is of even older origin, ultimately deriving from the Latin ingenium , meaning