Technical jargon: What does "cohort" actually mean?

In times of Corona, virologist lingo spreads almost as fast as the virus itself. Virologists, led by Germany's most popular, Christian Drosten of Berlin's Charité, often talk about the Munich Cohort study and other epidemiological cohort studies to explain the containment of a spread of the virus.

But this almost antiquated word has not only made its way into marketing lingo since Corona. No sooner have we understood that talking about target groups is no longer so en vogue in marketing, but rather about stakeholder groups or personas, than the next word appears: cohort, which originally comes from military language.

Suspicious characteristics and behavior

But instead of talking about the military subunit of a Roman legion, some talk about Ischgl tourists, Bergamo Champions League match-goers, or even the Munich cohort as viral hotspots. The others show customer cohort diagrams with total revenues, over several time periods, broken down by customer acquisition cohorts. Excuse me? In medicine, cohorts enable conclusions about biological or medical relationships. In marketing, what companies can expect from their existing or to-be-acquired customers based on their behavior. In both cases, it is simply a matter of groups of people and their common characteristics over a certain period of time, which they transmit in their contact networks. Virologists can explain, but not prevent, the fact that cohorts cripple not just individual countries, but the entire planet, and that not just a single company, but entire industries suffer as a result.