‘engine’

An engine in a car or aeroplane is such a solid, physical thing that it might be hard to imagine that the word engine has shown much development over its history. Instead, the history of engine is a curious one, and is a good example of a process which is common in English nouns: the transferral of what was once an abstract concept to something very concrete.

This original, abstract meaning of engine in English was ‘ingenuity, artfulness; cunning, trickery’; in the fourteenth century, the poet John Gower could write of women being ‘of great engyn’ in his Confessio Amantis.  From a modern perspective this sense can seem rather surprising, but this befits the word’s ultimate origins in the Latin word ingenium—from which the English ingenious is also derived.

From this sense, it was only a short step to applying engine to the products of such ingenuity. This could be something abstract, like a plan or plot, such as in Edward Gibbon’s ‘dark engines of policy’. More frequently, however, engine referred to a physical product of skill or ingenuity—to tools, implements, or devices.

At first, these engines were relatively simple, and could include anything from smaller objects, such as bows, nets, or ropes, to larger ones, such as catapults or torture racks. This broad sense remains current in English only in isolated cases, such as in fire engine, which originally referred to any apparatus used to put out fires (including buckets, ladders, and ropes), and, oddly, in fishing contexts:

2002 Irish Times (Nexis) 20 Mar. 26 In its first year of operation, 13 owners of 23 fishing engines (nets and traps) have agreed to cease fishing on a permanent basis.

However, apart from these few vestigial uses, engine began from the sixteenth century to be applied less frequently to simple implements and more often to complicated machines, ones with many moving parts, which were used to produce some physical effect. These could be anything from clocks to mills to pumps, but later engine more specifically came to refer to the steam engine, which performed the particular function of converting the energy of boiling water into motion.

These steam engines could be stationary ones, imparting motion to other machinery. Or they could be given wheels and used to pull heavy goods, as in a locomotive engine or traction engine. They could also, most pertinently from a modern point of view, be fitted into a vehicle in order to make it move. The first example of this sense recorded in the revised OED entry is of a steam engine fitted to a boat:

1813 Niles’ Weekly Reg. (Addenda section) 5, I have lived to see boats succeed well with those engines.

This sense was also applied to the equivalent parts of other vehicles, notably cars and (later) aeroplanes. As such methods of transport became vital to twentieth century life, this sense of engine became the dominant one. These engines were, of course, no longer driven by the energy of steam; instead, it was internal combustion engines and jet engines which were now the usual type.

Over a 500-year period, then, engine had completed a shift from its original abstract meaning of ingenuity, to be applied to simple tools and implements, then complicated machinery with many moving parts, and finally to the part of a vehicle which gives it motion. But the development of engine did not stop there. Instead, this mechanical concept of an engine as ‘something which causes something to move or to go’ has influenced (again abstract) figurative uses applied to anything considered a ‘driving force’ in some way, from ballerinas to football players to countries:

1977 I. Woodward Ballet iv. xviii. 201 The motive power is the music; the dancers are the engine.

2002 M. Crick Boss (2003) xvi. 280 The all-round player – a tackler, passer, runner, midfield engine, and inspirational team leader of great stamina.

2003 Kiplinger’s Personal Finance June 51/2 China is the big story here and the only engine of growth in the world economy at the moment.

The physical, solid concept of an engine has also, within the last few decades, transferred to the non-physical digital world. The old sense of ‘a complicated machine with moving parts, for producing a given physical effect’ has influenced (via Charles Babbage’s difference-engine and analytical engine) a sense newly recorded in the OED of ‘a piece of hardware or software with a specific computational function’. But although the technology has changed, the search engines of today still represent the product of much human ingenuity.