rhu in English dictionary RHU Meanings and definitions of "rhu" abbreviation (dictionaries) Random House Dictionary of the English Language Unabridged noun (space science, robotics) Initialism of [i]radioisotope heater unit[/i]. (a device that generates heat from the natural decay of radioactive material) more Grammar and declension of rhu RHU (plural RHUs) more Rhu rhu Sample sentences with "rhu" Declension Stem Try again Available translations French Irish Spanish Authors