Isotope of Bore-on (q.v.) with the half-life of a wet Bank Holiday.

An element that has the most disturbed orbital state of all, formed by the transmutation of chaotic isodopes.

An element that needs to be excluded, on principle, from the Periodic Table, say some. Its specific hazards are described in the tome-like treatise "The Perils of Paulinium" , by Dudley Doright.

A material suited to building the circuitry of an artificial intelligence. (Silicon is clearly capable only of artificial stupidity.)

A source of sheerly, starkly unthinkable coruscating lambent beams of unstoppable energy, and an essential catalyst in the manufacture of unobtanium.