AGK may refer to:
Agkistrodon piscivorus is a venomous snake, a species of pit viper, found in the southeastern United States.
Agkistrodon contortrix is a species of venomous snake endemic to Eastern North America, a member of the Crotalinae (pit viper) subfamily.
Agkistrodon is a genus of venomous pit vipers found in North America from the United States south to northern Costa Rica.
Common names: cantil, Mexican cantil, Mexican ground pit viper, Cantil viper, black moccasin, Mexican moccasin, more.
Common names: northern copperhead, copperhead, highland moccasin, more.
Common names: western cottonmouth, water moccasin, cottonmouth, more.
The human gene AGK encodes the enzyme mitochondrial acylglycerol kinase.
Agkistrodon piscivorus conanti, the Florida cottonmouth or green-tailed moccasin, is a venomous pitviper subspecies found in the southeastern United States, and Florida in particular.
Common names: broad-banded Copperhead, Texas copperhead, more.