homely
intimate
à deux
privately
close-tiled
in petto
have a quiet word
have a word in someone's ear
esoteric
private message
private
privy
secret
in secret
tête-à-tête
privateness
under the rose
proprietary
nonprivate
closet
prep school
powwow
personal life
preparatory school
hoard
in camera
home school
inquiry agent
seminary
offline
inside
in confidence
heart of hearts
interiority
inwardly
private dick
snoop
eavesdropping
tete-a-tete
head-to-head
behind closed doors
closeting
chamber
heart-to-heart
confidential
academy
sit in on
by-interest
knowing
auricular