There’s a lovely pattern to these words, which come from astronomy:
| near | far | |
| perigee | apogee | (Earth) |
| perihelion | aphelion | (Sun) |
| perijove | apojove | (Jupiter) |
| perisaturnium | aposaturnium | (Saturn) |
| periapsis | apsis | (any body) |
The perigee, for example, is the nearest point to Earth on some orbit, and the apogee is the farthest point on such an orbit. (Thanks to Garth of perijove.com for pointing this out to me.) The apogee is also the peak of a trajectory, which is of course also the farthest point from Earth on an “orbit”; and metaphorically, the apogee can be the best point of something, like a career.
I didn’t recognize the peri- or apo- prefixes before this investigation, but there are lots of words that use them. Peri- is used a lot by anatomists to refer to areas close to something in the body—I read about the "perisylvian region" of the brain, which is adjacent to the Sylvian fold, one of the many folds of the brain. Apo- means “away,” generally, and here are some interesting uses:
| apostle | (one who is sent out, a messenger) |
| apotropaic | (something that turns away evil, as stone lions and gargoyles) |
| apostate | (one who stands away) |
| apocalypse | (literally, a revelation, or veil-away) |
Sadly I couldn't find any more pairs as in the first table.
In nursing "peri-" is usually used to refer to the taint in some way: perineal, peri-wash, peri-care.
Also, apoptosis led me to blebbing." That be funny!
Now that you mention it, ptosis is its own thing...it means drooping eyelids. Perhaps the word has to do with things becoming amorphous or bulging, and that's how it got applied to cell lysis? I'll have my people look into it.