bio

Two Greek words for life

Greek kept bios and zoe apart with some care. Zoe was life as a condition — the opposite of death — and is the word used in zoology and in the name Zoe itself. Bios was a life as a particular thing: a span, a career, a way of living, the thing you describe when you tell someone's story.

That distinction is why the two most familiar English bio-words point in different directions. Biology, with logos, is the study of living things in general, a science. Biography, with graphein, is the writing of one life, a genre. Both were coined within a few decades of 1800, and both were built by naturalists and men of letters who knew exactly which Greek word they were using.

The prefix turns technical

Chemistry, medicine and ecology then took the prefix and made it ordinary. Biochemistry (1880s) studies the chemistry of living matter; biosphere (1875, coined by Eduard Suess) treats the living layer of the planet as a single object; biodiversity appeared in the 1980s when the conservation movement needed a word for what it was trying to protect.

Medicine built a parallel set with a slightly darker tone, since many of its words describe what goes wrong: biopsy (a look at living tissue), biotoxin, biocide, and the various -biotics that either kill or support bacteria. All still carry the Greek word for life, even when the life in question is being removed.

• biology — 1802 by Lamarck and Treviranus independently
• biography — 1660s, at first for a written life in the general sense
• biochemistry — 1880s, the chemistry of living matter
• biosphere — 1875, Suess's term for the living layer of the Earth
• biodiversity — 1980s, coined for the conservation movement
• biopic — 1950s, a Hollywood clipping of biographical picture

False friends on the same stem

The prefix is so attractive that it has been attached to words where it means almost nothing — bioterrorism is terrorism, biometrics is measurement — but in each case the bio- element is doing real work, since the target or the object is a living body.

Two traps are worth naming. Symbiosis is "living together" and is used in business writing as a loose synonym for cooperation, though biologists use it strictly. And antibiotic is often misread as meaning "anti-illness"; the -biotic element comes from biotikos, "of life", and the word was coined in 1941 for substances that kill bacteria.