Architecture Style
A named, coarse-grained way of organising a whole system, as distinct from a pattern that solves one recurring problem inside it.
Styles are system-level: layered, event-driven, microservices, pipe-and-filter, space-based, microkernel. Patterns are problem-level: saga, circuit breaker, sidecar, CQRS.
The distinction is worth keeping because they compose differently. A system has one dominant style (occasionally two in different subsystems) and many patterns. "We use microservices and CQRS and the saga pattern" is coherent; "we use microservices and layered architecture and event-driven" usually means nobody has decided.
Choosing a style is choosing which quality attributes get cheap and which get expensive. Event-driven makes decoupling and scalability cheap and makes end-to-end reasoning and transactional consistency expensive. There is no style that makes everything cheap.