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