Meanings

earth orbit

heliocentric orbit

periarthritis scapulohumeralis

second anniversary of a death

Suō (former province located in the southeast of present-day Yamaguchi Prefecture)

processor frequency

inner circumference

periodic comet

long-period comet

short-period comet

when you really think about it

perinatal medical center (centre)

solar cycle

going around the entirety (of a place)

intermediate frequency

high frequency

lunar orbit

orbit

periderm

diurnal