Something of unnatural size, shape, or quality; a prodigy; an enormity; a marvel, Any thing or person of unnatural or excessive ugliness, deformity, wickedness, or cruelt, A terrifying and dangerous, wild or fictional creature, adjective_ Very large; worthy of a monster, Informal Extremely large; monstrous, verb_ To make into a monster; to categorise as a monster; to demonise, To harass, To behave as a monster to; to terrorise, transitive verb_ obsolete To make monstrous