(Greek mythology, Roman mythology) Of or relating to Pluto, the Greek and Roman god of the underworld; demonic, infernal.

(geology, historical) A proponent of plutonism; a plutonist.

(astrology) Pertaining to the astrological influence of Pluto, formerly regarded as a planet. / (astronomy) Of or relating to the dwarf planet Pluto.

(astrology) A person under the astrological influence of Pluto, formerly regarded as a planet. / (chiefly science fiction) An (imaginary) inhabitant of the dwarf planet Pluto.

plural of Plutonian