Expand your word power

I have an extreme and inexplicable fondness for the word "perijove,"—probably because I've always been intrigued by words in which an adjectival or compound form uses a different root. For example "Mancunian" (someone from Manchester) or "Jacobian" (from the era of King James). Mostly because they're not at all intuitive—you just have to know.

Perijove refers to the closest approach of an orbiting body to the planet Jupiter ("Jove" being the greek version of the god's name, by Jove). Just as we have perigee/apogee for the Earth, perihelion/aphelion for the Sun, and periastron/apastron for other stars, you can extrapolate the formula to get similar constructions for the other celestial bodies:

Saturn: perisaturnum/perikrone
Moon: periselene/perilune
Mercury: perihermion
Tom Cruise: peripleo*

Wikipedia has a pretty comprehensive rundown.

* Actually, this was more apt than I intended because, of course, "cruise" already means to traverse or circumnavigate.