Of the named ocean, and peaceable. Named by a sailor who found it calm on the day he crossed.
Latin pacificus (peace-making), from pax (peace) + facere (to make); Ferdinand Magellan named the ocean in 1521 for the calm he met crossing it, and the name has carried both senses — the sea and the disposition — ever since.
Calm enough, on the day it was named, to give an ocean its temperament as well as its place on the map.