Gigantism and acromegaly are two disorders with the same disease mechanism and somewhat similar presentations. Even though they have the same disease mechanism, the two have entirely different outcome simply due to the age of onset. Gigantism is the result if the disease mechanism starts in childhood.
Adult Velociraptors grew up to 6.8 feet (2 meters) long, 1.6 feet (0.5 meter) tall at the hip and weighed up to 33 pounds (15 kilograms).
Megalodons were, as we know, freaking huge. Some of the teeth discovered from this whopping great predator have been over 17 centimeters (7 inches) in total height, but the majority are between 3 and 5 inches (still, massive).