transcendental

Concise Oxford English Dictionary © 2008 Oxford University Press:
transcendental/transenˈdentl/

▶adjective

• 1 relating to a spiritual realm.

  ■ relating to or denoting Transcendentalism.

• 2 (in Kantian philosophy) presupposed in and necessary to experience; a priori.

• 3 Mathematics (of a quantity or function) not capable of being produced by the algebraical operations of addition, multiplication, and involution, or the inverse operations.

– derivatives
transcendentalize (or transcendentalise) verb,
transcendentally adverb.