Cohort

Definition 1:  A group of persons who experience a certain event in a specified period of time. For example, the birth cohort of 1985 would be the people born in that year.

Source: OECD Glossary of statistical terms. In Handbook of Vital Statistics Systems and Methods, Volume 1: Legal, Organisational and Technical Aspects, United Nations Studies in Methods, Glossary, Series F, No. 35, United Nations, New York 1991.

HYPERLINK: http://stats.oecd.org/glossary/detail.asp?ID=376

Definition 2:  A group of people sharing a common demographic experience who are observed through time. The cohort of persons born in the same year is known as a generation, while the cohort of persons married in the same year is called a marriage cohort or a marriage generation.
Source: Eurostat's Concepts and Definitions Database, RAMON- Eurostat, European Union.

HYPERLINK: http://ec.europa.eu/eurostat/ramon/nomenclatures/index.cfm?TargetUrl=LST_NOM_DTL_GLOSSARY&StrNom=CODED2&StrLanguageCode=EN

Definition 3:  Group of persons who jointly experience a series of events over a period of time. A school cohort is defined as a group of pupils who enter the first grade of a given cycle in the same school year.

Source: UIS Glossary, UIS- UNESCO.
HYPERLINK: http://uis.unesco.org/en/glossary