Our paid praters have been killing off metaphors for years, to a degree at which one would almost think they were in the business of metaphorslaughter, rather than the business, directly or indirectly, of selling. A favorite method for killing metaphors is to use a dramatic word where only a plain one is called for. This word-inflation presumably is intended to excite the listener and to stimulate the purchase-response in the autonomic nervous system; but its lasting effect is to debase the currency, as it were, leaving once-vivid expressions lifeless and no more meaningful than the plainer words they have displaced.
Impact is the classic victim of this method. The noun, impact, once connoted force; it referred to a violent collision of physical bodies. An asteroid made impact on the earth’s surface. A skidding car made impact against a telephone pole. An impact drill drove its bit into masonry with blows from a hammer.
The verb, to impáct, correspondingly, connoted forcible collision or impingement. (Impact and impinge come from different forms of the same Latin word, impingo [infinitive, impingere], to push, strike, or drive at or into any thing; to thrust, strike, or dash against; participle, impactus.) Wisdom teeth could become impacted because the force of their growth drove them hard against the adjacent molars.
In those days, to say that something had “made an impact” was to employ a metaphor: the thing described—an idea, an event, an invention—had struck something or somebody—the public, the speaker, the business world—with unusual force, as if it were a physical object that had plunged from a great height or been fired from a gun.
Today, that metaphor is dead, drained of its force by overuse in expressions describing mere effect. In fact, one is far more likely nowadays to hear, “It had an impact;” than “It had an effect;” regardless of whether the effect in question was unusually forcible—i.e., was comparable to a literal impact—or not. The dead noun has also spawned a dead verb, to ímpact, meaning, “to have an effect” on somebody or something, but without any connotation of force.
Another casualty of word inflation has been implode. Like impact, implode and implosion used to connote force. An implosion was like an explosion, only in the opposite direction. When a thing imploded, it collapsed violently into its center, as we were always warned TV picture tubes would do, with deadly force, if they were ever cracked.
Then the paid praters got ahold of it. For a while, a report of the implosion of, say, a government or social movement told us of its catastrophic failure, usually from internal flaws or forces, and often with disastrous consequences for those involved. Now, however, to implode is simply to collapse, to fall apart, to fail. Repeated misapplication has killed another metaphor.
A somewhat similar case is that of epicenter, a casualty of the nuclear age. Epicenter combines a common English noun, center, with the Greek prefix epi-, meaning on, at, besides, to describe a place that is not the center, but lies in some definite relation to the center—usually above it.
We speak of San Francisco or Kabul as the epicenter of an earthquake because the actual center of the quake lay deep within the earth, and the place we really care about is high above it, on the surface, where all the destruction and human misery took place. We also hear of the epicenter of a nuclear explosion, usually an erroneous reference to its hypocenter (Gk. hypo- = below, beneath, down), the spot on the earth’s surface directly below the actual center, which is usually some miles up in the sky. (An underground nuclear explosion, of course, would have an epicenter on the surface.) I suspect that this association with the atomic bomb is what has made the term so popular in modern times. After all, there have always been earthquakes, but other events have not always had epicenters.
Once upon a time, epicenter could be used metaphorically to refer to a locus of furious activity, analogous to the epicenter of an earthquake. The best examples would have referred, not to the center of the phenomenon in question, but to a place above, or at any rate outside, the center, where important or vigorous activity ancillary to the main phenomenon took place. Thus, the epicenter of a political convention might be, not the podium, but the caucus room behind the stage. Alternatively, and perhaps better, a writer might make the caucus room the center of the convention’s drama, and the podium the epicenter, where the effects of what happened in the caucus room were made manifest.
These days, however, epicenter is a dead metaphor, and the saddest kind of dead metaphor, because it was killed, not through overuse as a metaphor, but through perfectly prosaic ignorance: it died of augmentation disease.
Augmentation disease is caused by the solecistic annexation of particles to a word, apparently upon the presumption that they intensify the root meaning, or otherwise add importance to the word (give it more impact, as it were).
As we most commonly encounter the word today, epicenter is merely center with augmentation disease. It never carried a metaphorical sense: it never meant anything but plain old center—or, at best, “the very, very center“. The paid praters added epi- just for the sake of novelty or intensity, and thereby quickly robbed it of both.
Sic transit gloria linguae Anglorum.