the.com/occult
Knowledge hidden in plain sight, mostly because nobody could find the receipt.
means Relating to supernatural, mystical, or magical beliefs and practices, especially those kept secret from outsiders.
from From Latin occultus, hidden or concealed, past participle of occulere, to cover over — originally a verb about literally covering things up, later about covering up cosmic secrets.
Astronomy termAn occultation is one body hiding another, no spells required.
Medical meaningOccult blood means hidden, detectable only by lab tests.
Victorian crazeSeances and Ouija boards turned the occult mainstream.