(n.) Plural of Arcanum.

abstract abstruse airy anagogic apply to arcana arcane arcanum asomatous astral baffling becloud beclouded bedarken bedim befog begloom between the lines black black magic black out blacken blanket blind block block the light blot out bodiless bodilessness brown buried bury cabala cabalic cabalism cabalistic cabbala cabbalism cabbalistic cache camouflage canopy cast a shadow censored classified classified information cloak close closed clothe cloud cloud over clouded conceal concealed confidence confidential communication cope cover cover up covered covert cowl dark darken darken over decarnate decarnated deep delitescent dim dim out discarnate disembodied disguise dissemble distract attention from ditch dormant eclipse eclipsed eerie eeriness elfdom encloud encompass with shadow enigma enigmatic ensconce enshroud envelop esoteric esoterica ethereal extramundane extraterrestrial faerie fey film ghostliness ghostly gloom gloss over guarded secret heavy hermetic hermetics hibernating hid hidden hide hood hush-hush hypernormal hyperphysical immaterial immateriality immaterialness impalpability impalpable impenetrable imponderability imponderable in a cloud in a fog in eclipse in purdah in the wings incommunicado incomprehensible incorporate incorporeal incorporeality incorporeity indecipherable inexplicable inextension inscrutable insubstantial intangibility intangible keep under cover latent lay on lay over lurking magical mantle mask metaphysic miraculousness muffle muffled murk mysterious mysteriousness mystery mystery of mysteries mystic mystical mystifying nonexteriority nonmaterial nonphysical numinous numinousness obduce obfuscate obfuscated obnubilate obscure obscured obumbrate occult phenomena occultate occultism otherworldliness otherworldly overcast overcloud overlay overshadow overspread perplexing personal matter phantom possible potential preterhuman preternatural preternaturalism preternormal pretersensual private private matter privileged communication privity privy profound profound secret psychic psychical research psychicism psychics psychism put on puzzling recondite restricted restricted information screen scum sealed book secluded secluse secret secrete sequestered shade shadow shadowiness shadowy shield shroud shrouded sleeping slur over smothered somber sorcery spirit world spiritual spirituality spirituousness spread over stash stifled submerged superhuman superhumanity superimpose supernatural supernaturalism supernaturality supernaturalness supernature supernormal supernormalness superphysical superphysicalness superpose supersensible supersensibleness supersensual