What does "hieroglyphic" mean?

Hieroglyphic: Any character or figure which has, or is supposed to have, a hidden or mysterious significance; hence, any unintelligible or illegible character or mark. [Colloq.]

Additional senses

  1. 2.Emblematic; expressive of some meaning by characters, pictures, or figures; as, hieroglyphic writing; a hieroglyphic obelisk. Pages no better than blanks to common minds, to his, hieroglyphical of wisest secrets. Prof. Wilson.
  2. 3.Resembling hieroglyphics; not decipherable. "An hieroglyphical scrawl." Sir W. Scott.

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