"Fire belly" typically refers to an amphibian, the fire-bellied toad, with bright orange or red markings on its belly. However, if we explore antonyms for this phrase, we might think of animals with contrasting colors, such as the snow leopard or the albino alligator. We could also consider words that evoke coolness and water, such as "icy" or "aqua." Alternatively, we could focus on opposite sensations, like "calm" or "peaceful," which bring to mind tranquil landscapes and serene animals such as swans or deer. Ultimately, the antonyms of "fire belly" offer a range of possibilities for creating exact and evocative descriptions.