keep quiet
hush up
keep
keep a lid on
keep one's mouth shut
keep one's lips sealed
keep to oneself
tick a lock
secret
keep one's counsel
let the cat out of the bag
cryptadia
button one's lip
keep mum
disembosom
secrecy
give away
keep from
on the QT
secretly
conceal
on the Q.T.
in secret
keep shtum
stall
secretiveness
silence
sensitive
concealment
covert
oyster
shut one's mouth
transpire
mum's the word
hiding
concealing
stifle
under wraps
between you and me
darkness
hush-hush
sing like a bird
evasive
semisecretly
cloakedly
secretness
semisecret
steal
close ranks
oversecrete
one's lips are sealed
hidingly
closehandedness
keep shady
subterraneous
subterranean
ulterior
secernent
confidentiality
unsecretly
secretively
on the down-low
get wind of
inform on
under the covers
hugger-mugger
backroom
closet
sub rosa
Deep Throat
hideling
secretive
confidable
lie low
underhand
something nasty in the woodshed
on the hush
confide in
tomb
feign
hold one's tongue
hidelings
closehanded
breast one's cards
hidness
under the radar
under one's hat
private
aboveboard
guard one's tongue
straightforward
disguise
antisecrecy
shoot off at the mouth