abstruseness
arcanum
cabala
classified information
complexity
complication
confidence
confidential communication
crabbedness
crampedness
deepness
difficulty
enigma
guarded secret
hardness
hermetics
intricacy
knottiness
mystery
mystery of mysteries
personal matter
private matter
privileged communication
privity
profound secret
profoundness
profundity
reconditeness
restricted information
sealed book
secret
the occult
esoteric
exoteric
exoterica
astrophysicist
breeching
egalitarianism
fire-eater
formulæ
hocus-pocus
hotseat
indissolubility
justiwcation
matters
maximums
occurence
operandi
piwafwi
postulation
rabbit-hole
roboticist
scrying
speciousness
theosophist
warhammer
z