Oneirology is the scientific study of dreams. The word oneirology is derived from the Greek words "oneiros" and "logos," meaning dream and study, respectively. Synonyms for oneirology include sleep research, dream analysis, dream science, and somnology. Each of these terms refers to the study of topics related to sleep, dreams, and their impact on the brain and body. Sleep research encompasses the study of sleep cycles, disorders, and the relationship between sleep and health. Dream analysis deals with the interpretation of the content and symbolism of dreams, while dream science describes the scientific methods used to study sleep and dreams. Somnology focuses on the medical aspects of sleep and sleep disorders.