This is a review of the book "A Dictionary of Epidemiology" edited by Miquel Porta. The book is a revised and updated version of a classic text, sponsored by the International Epidemiological Association (IEA). It is the definitive dictionary of epidemiology. The new edition, edited by Miquel Porta, succeeds John Last. It includes a large number of new terms, illustrations, and a new and fresh design. The book provides definitions and explanations of both common and advanced epidemiological terms, as well as most of the most recent methodological innovations. The fifth edition has also expanded its objective to include epidemiological methods in clinical research, public health practice, genetics, and social sciences. New terms from biostatistics, clinical epidemiology, environment, sociology, and life cycle epidemiology; genetic and molecular epidemiology, health promotion, preventive medicine, health economics, and bioethics are included. In summary, the book includes scientific terms relevant to clinical medicine, public health, and other social, health, and life sciences. Anyone seeking clarity on epidemiological definitions and methodological aspects related to human health will find this book invaluable. In epidemiology, there is nothing like this text.This is a review of the book "A Dictionary of Epidemiology" edited by Miquel Porta. The book is a revised and updated version of a classic text, sponsored by the International Epidemiological Association (IEA). It is the definitive dictionary of epidemiology. The new edition, edited by Miquel Porta, succeeds John Last. It includes a large number of new terms, illustrations, and a new and fresh design. The book provides definitions and explanations of both common and advanced epidemiological terms, as well as most of the most recent methodological innovations. The fifth edition has also expanded its objective to include epidemiological methods in clinical research, public health practice, genetics, and social sciences. New terms from biostatistics, clinical epidemiology, environment, sociology, and life cycle epidemiology; genetic and molecular epidemiology, health promotion, preventive medicine, health economics, and bioethics are included. In summary, the book includes scientific terms relevant to clinical medicine, public health, and other social, health, and life sciences. Anyone seeking clarity on epidemiological definitions and methodological aspects related to human health will find this book invaluable. In epidemiology, there is nothing like this text.