Teuthology (from Greek τεῦθος, "cuttlefish, squid", and -λογία, -logia)[1] is the study of cephalopods. Cephalopods are members of the class Cephalopoda in the Phylum Mollusca. Some common examples of cephalopods are octopus, squid, and cuttlefish. Teuthology is a large area of study that covers cephalopod life cycles, reproduction, evolution, anatomy and taxonomy.
Teuthology is a specific branch of malacology, the study of molluscs, in marine zoology. A teuthologist is a scientist who studies teuthology.