e23

E23 is a designation used in a variety of unrelated systems to label different objects, routes, or time points. It does not refer to a single entity, and its meaning depends on the domain.

In transportation, E23 denotes a route in the European E-road network. European routes use the E prefix and a number to indicate transnational corridors. The specific alignment of the E23 has changed over time as infrastructure and policies evolve, and local signage reflects the current designation within each country.

In developmental biology, E23 commonly marks embryonic day 23 in laboratory animals such as mice and rats. Researchers use these day labels to stage development and coordinate experiments, with E23 representing a late embryonic stage before birth in many species.

In technology and industry, E23 appears as a model number, product code, or catalog identifier. It may convey information about a product family, version, or component, but the exact meaning depends on the manufacturer and context.

This multiplicity of uses illustrates how alphanumeric designations are repurposed across fields, requiring domain-specific clarification to interpret E23 correctly.