The term "shadow dragon" refers to a mythical creature that has the ability to manipulate darkness and shadow. Many words can be used as synonyms for "shadow dragon," including obsidian wyrm, umbral drake, and nocturnal serpent. Other options include gloom wyvern, darkened basilisk, and shade wyrm. These synonyms all evoke the idea of a powerful and dangerous creature steeped in shadows and darkness. Some other possible synonyms include ebony wyrm, dusky drake, and night serpent, each conveying a different aspect of the shadow dragon's myth and legend. Overall, these synonyms reflect the eerie, mystical, and fearsome qualities of these legendary creatures.