Synonyms of the word

hidden

• v. past participle of hide.
• adj. That has been moved out of sight. Invisible or unapparent.
• adj. Obscure.
• adj. That has been hidden.

concealed

• v. simple past tense and past participle of conceal.

invisible

• adj. Unable to be seen; out of sight; not visible.
• adj. Not appearing on the surface.
• adj. (Internet) Apparently, but not actually, offline.
• adj. (psychology) That is ignored by a person.
• v. To invisiblize.
• n. (obsolete) An invisible person or thing; specifically, God, the Supreme Being.
• n. (obsolete) A Rosicrucian; so called because avoiding declaration of his craft.
• n. (obsolete) One of those (as in the 16th century) who denied the visibility of the church.

obscure

• adj. Dark, faint or indistinct.
• adj. Hidden, out of sight or inconspicuous.
• adj. difficult to understand.
• adj. not well-known.
• v. (transitive) To render obscure; to darken; to make dim; to keep in the dark; to hide; to make less visible,…
• v. (transitive) To hide, put out of sight etc.
• v. (intransitive, obsolete) To conceal oneself; to hide.

secret

• n. (countable, uncountable) Knowledge that is hidden and intended to be kept hidden.
• n. (uncountable) Something not understood or known.
• n. (archaic, in the plural) The genital organs.
• adj. Being or kept hidden.
• adj. (obsolete) Withdrawn from general intercourse or notice; in retirement or secrecy; secluded.
• adj. (obsolete) Faithful to a secret; not inclined to divulge or betray confidence; secretive.
• adj. (obsolete) Separate; distinct.
• v. (transitive) To make or keep secret.
• v. (transitive) To hide secretly.

unseeable

• adj. invisible.
• adj. unimaginable.