The term "service mesh" refers to a configurable framework in cloud-native development that manages communication between microservices. It provides a dedicated infrastructure layer to handle service-to-service interactions, ensuring features like load balancing, service discovery, and security policies are efficiently managed. By abstracting network complexity, a service mesh enables developers to focus on building application logic without worrying about the underlying communication details. This enhances application resilience, promotes observability, and simplifies the operations of distributed systems, making it vital for modern application architectures.