ALAM AL-MITHAL: the mystical world of similitudes where all physical limitations are removed.
He wondered it if might be possible that his ruh-spirit had slipped over somehow into the world where the Fremen believed he had his true existence — into the alam al-mithal, the world of similitudes, that metaphysical realm where all physical limitations were removed.
There are no more uses of "similitude" in the book.
Show samples from other sources
People are drawn to communities of similitude.
the dream had too much similitude of the fact
Daniel Defoe -- The Further Adventures of Robinson Crusoe