H. gigas

H. gigas may refer to:
 * Harpactira gigas, a tarantula native to South Africa
 * Hippotragus gigas, an extinct species of antelope
 * Holmskioldia gigas, a flowering plant species found in Kenya and Tanzania
 * Hyaenodon gigas, an extinct mammal species
 * Hydrodamalis gigas, an extinct sirenian
 * Hydrodynastes gigas, a rear-fanged venomous colubrid species found in South America
 * Hysterocrates gigas, a tarantula native to Cameroon