shadow history
clandescent
secretomics
open secret
ectocrine
top secret
secretomal
underhand
occult
mum
crypto-
secretive
dark
off-the-record
out with it
tomb
closehanded
occultive
disclosed
under the covers
on the down-low
qabalistic
cabalistic
secretomic
covert
cryptical
sibylline
kabbalistic
tip one's hand
cryptic
disclosure
concealment
secretional
secretionary
underwrapped
secernent
leak
subterranean
backroom
skeleton in the closet
occulted
skeleton in the cupboard
supersecret
blow the lid off
espionage
let the cat out of the bag
data hiding
back street
keep a lid on
hideling
secrecy
significant
mysteriosophy
lithia emerald
cryptadia
secretly
hugger-mugger
top-secret
whisperer
divulgation
secret of Polichinelle
confidentiality
closeness
shoot off at the mouth
something nasty in the woodshed
confidence
pseudosecret
get wind of
hidingly
clandestinely
secret
transpire
out
occultation
exposure
divulgence
hiding
secretively
let something slip
concealing
divulgement
behind the scenes
veiledly
on the hush
in petto
under wraps
let on
break
reveal
expose
uncover
bring out
let out
unwrap
discover
divulge
anecdote
disclose
give away