calm
composed
at peace
at rest
blank
blankminded
bloodless
cloistered
collected
concordant
cool
coolheaded
dispassionate
dwindling
easy
easygoing
ebbing
empty
empty-headed
equable
even
even-tempered
even-tenored
fatuous
halcyon
hushed
idyllic
impassive
inane
incogitant
irenic
isolated
levelheaded
moldering
nirvanic
oblivious
orderly
pacific
passive
pastoral
peaceable
peaceful
peacetime
philosophical
piping
placid
poised
possessed
tranquillity
tranquillize
tranquilly
tranquilness
blissful
dreamy
gracious
heavenly
manly
restful
serene
sober
sunny
undisturbed