“The whole is greater than the sum of its parts” expresses the essence of *holism*, a term coined by the great South African general and statesman Jan Smuts in 1926. Holism generally opposes the Western tendency toward analysis, the breaking down of wholes into parts sometimes to the point that “you can't see the forest for the trees.” Holism is an important concept in the sciences and social sciences, and especially in medicine. Holistic medicine tries to treat the “whole person” rather than focusing too narrowly on single symptoms. It emphasizes the connections between the mind and the body, avoids the overuse of drugs, and has borrowed such practices from Eastern traditions as acupuncture and yoga.

A three-dimensional image reproduced from a pattern of interference produced by a beam of radiation such as a laser.

A hologram is a picture of a “whole” object, showing it in three dimensions. We've all seen cheap *holographic* images on credit cards andID cards (where they help prevent copying). Far more impressive are large holograms that take the form of a ghostly 3-D moving figure that you can walk around to see from all angles. Holograms were invented in 1947 but only perfected after the invention of the laser in 1960. Today they're used in such technologies as compact-disc players and checkout scanners, and holograms can be created of the inside of live internal organs to permit doctors to examine the organs in great detail. And soon televisions with hologram technology may enable us to watch in “3-D.”

Of, relating to, or being the present geologic epoch.

To geologists, we live today in the Holocene epoch, the period that began about 10,000 years ago, at the end of the last ice age, when humans first began practicing agriculture. But what does Holocene have to do with “whole”? Well, in geological language, the Holocene epoch follows the *Paleocene* (“remotely recent”), the *Eocene* (“early recent”), the *Oligocene* (“scarcely recent”), the *Miocene* (“less recent”), the *Pliocene* (“more recent”), and the *Pleistocene* (“most recent”) epochs—so the Holocene is the “wholly recent” period of geological time.

(1) (usually capitalized) The mass slaughter of European civilians and especially Jews by the Nazis during World War II. (2) A thorough destruction involving extensive loss of life, especially through fire.

The Greek word *holokaustos* means “burnt whole.” For the early Jews who followed the laws given in the first books of the Bible, a holocaust was a sacrifice to God, the burning on an altar of a lamb, goat, or young bull. The word is used about 200 times in the traditional Greek version of the Old Testament, though it rarely appears in English translations. In the 1700s *holocaust* began to be used to refer to the mass destruction of life. But no mass murder in Western history ever approached the scale achieved by the Nazis. As many as 6 million Jews may have died at their hands; when the slaughter of non-Jews is included, the number of murdered victims may have amounted to over 15 million.

Intended to apply or take effect at a date in the past.

We normally think of time as constantly moving forward. Since *retroactive* seems to defy time's forward movement, retroactive taxes, laws, and regulations are often seen as particularly obnoxious and unfair. (See also *ex post facto*.) But nobody ever objects to receiving a retroactive raise at work. When we judge historical people and events in terms of present-day morality and attitudes, our retroactive judgments may indicate that we're too impressed with ourselves and ignorant of history.

To furnish something with new or modified parts or equipment that was optional or unavailable at the time of manufacture.

The concept of retrofitting became an urgent necessity during World War II, when weapons technology was advancing at an intense pace and planes and ships were becoming outdated even before their construction was complete, and the only solution was to retrofit the completed craft with the brand-new technology. Retrofitting was revived on a massive scale during the energy crisis of the 1970s, when new features were added to millions of old houses to make them more energy-efficient. Retrofitting is thus different from merely *renovating*, which may not involve any new technology at all.

To return to an earlier and usually worse or more primitive state.

As you might guess, *retrogress* is the opposite of *progress. Retrogression* is usually an undesirable decline from a higher or advanced level. So, for instance, in difficult social situations an adolescent can retrogress to a childish level of maturity. And under the extreme conditions of total war, a whole society may retrogress to a primitive state. The increasing number of poor or homeless people has been seen as evidence of modern social retrogression, and the rise of loud, name-calling TV and radio personalities strikes many people as a sign of political retrogression.

A generally comprehensive exhibition or performance usually covering an artist's output to date.

*Retrospective* is partly rooted in the Latin verb *specere,* “to look,” so a retrospective is a look back at an artist's career. The subject of a retrospective is usually an older living artist, or one who has recently died. Galleries and museums honor painters and sculptors, film festivals honor directors and actors, and concert organizations honor composers. Retrospectives can be difficult and expensive to assemble, so they're rarely put together except for deserving artists; the result is that they frequently win many new fans for the person's achievement.