Terminology

2185 terms, tools, patterns and metrics an architect is expected to use precisely. Each one gets a short explanation of what it is, and — where it matters — what it is commonly confused with. Search filters as you type; the column headers sort.

All areas2185 Architecture Fundamentals77 Distributed Systems107 Data Architecture110 Cloud Architecture89 Networking88 API & Integration Architecture82 Reliability & Resilience75 Observability70 Performance & Capacity Engineering72 Security Architecture81 Cost Architecture & FinOps66 Business Architecture67 Architecture Communication67 Enterprise Architecture66 Legacy Modernization66 AI-Era Architecture69 Software Architecture & Engineering71 Architecture Patterns71 Architecture Decision-Making63 The Architect's Meta-Skills61 Delivery & Release Engineering66 Platform Engineering & Developer Experience70 Testing & Quality Architecture66 Data Platform Architecture64 Streaming & Real-Time Data69 Data Governance & Semantics69 Frontend & Experience Architecture66 Edge, Mobile & IoT68 Regulatory & Data Protection Architecture65 Assurance, Audit & Model Risk64

Kind Any concept785 practice729 pattern362 metric125 case-study77 tool62 protocol45

785 terms shown.

Term	Kind	Topic	What it is
Absence-As-Delete Sync Full-Sync Delete Semantics, Destructive Sync	concept	Reverse ETL	A synchronisation mode that treats a record's absence from the source query as an instruction to remove or clear it downstream - so any query returning fewer rows becomes a mass deletion in a live operational …
Abstraction	concept	Architecture Fundamentals	Exposing what a component does while hiding how it does it, so callers depend on the contract rather than the mechanism.
Abstraction and Encapsulation	concept	Abstraction & Encapsulation	Hiding mechanism behind a contract so the mechanism can be replaced — and the discipline of not letting the mechanism leak through the contract.
Abuse Case Misuse Case	concept	Communicating Threat Models	A use case written from the attacker's side - a hostile actor plus the interaction that achieves their goal - which engineers can refute or fix, unlike a likelihood-impact score which they can only dispute.
Access Geography Access as Transfer, Remote Viewing	concept	Cross-Border Transfer	The recognition that viewing data from another jurisdiction is a cross-border transfer, which makes access control and the location of the people using it a transfer control.
Access Pattern Skew Popularity Skew, Zipf Distribution	concept	Caching for Performance	The uneven distribution of requests across keys - which determines whether caching helps at all, and which synthetic load tests systematically fail to reproduce.
Accidental vs Essential Complexity	concept	Architecture Fundamentals	Essential complexity comes from the problem and cannot be removed; accidental complexity comes from your solution and usually can.
Active-Active vs Active-Passive	concept	Multi-Region Architecture	Whether all regions serve traffic simultaneously, or one serves while another waits to take over — a choice about which failure mode you would rather have.
Additive-Only Evolution Non-Breaking Change Discipline, Tolerant Reader Contract	concept	API Versioning	Establishing the compatibility contract before the first release - unknown fields ignored, unknown enum values defaulted - so that most future change requires no version at all.
Administrative Path Blindness Support Tool Gap, Internal Access Blind Spot	concept	Authorization	The pattern where the customer-facing data path is rigorously access-controlled while internal dashboards, support tools, analytics jobs and exports have unrestricted access - protecting against the wrong adversary.
Agent Loop	concept	Agent Architectures	The cycle in which a model observes state, selects an action, executes a tool and observes the result, repeating until a goal or a limit is reached.
Alert Fatigue	concept	Observability	The desensitisation that follows from alerts that are frequent, non-actionable, or not tied to user impact — after which real alerts are missed too.
Alert Fatigue in Practice	concept	Alert Fatigue	The state in which alerts are ignored because most of them do not matter — a reliability failure caused by monitoring rather than prevented by it.
Alert on Symptoms Symptom-Based Alerting	concept	Alerting	Paging on user-visible impact rather than on internal conditions that may or may not cause it.
Ambiguity Tolerance	concept	Handling Ambiguity	The capacity to make progress on a problem before it is fully specified, which is the normal condition of architectural work.
Ambiguous Outcome Unknown State, Indeterminate Result	concept	Timeouts & Deadlines	The state a system is in when a call times out - not failure, but unknown - and the design obligation to have somewhere to put it.
Amdahl's Law	concept	Profiling & Optimisation	The limit on speedup from optimising or parallelising part of a system, set by the proportion of work that remains unchanged.
Anaemic Domain Model	concept	Domain-Driven Design	Objects that hold data with no behaviour, leaving business rules scattered across service classes where they are duplicated and inconsistently applied.
Analytical Estate Topology	concept	Data Platform Architecture	The full picture of where analytical data lands, is transformed and is served, including the paths that bypass the intended one.
Anycast	concept	Networking	Advertising the same IP address from many locations, so the network routes each client to the topologically nearest one.
Application Architecture	concept	Application Architecture	The set of applications, what each is responsible for, and how they relate — the view that reveals duplication and orphaned ownership.
Application Landscape	concept	Application Architecture	The inventory of systems in an organisation with their ownership, capabilities supported, integrations and lifecycle status.
Approximate Nearest Neighbour Index ANN	concept	Vector Databases	An index that trades exactness for speed when finding similar vectors, making large-scale semantic search feasible.
Architect Archetypes	concept	Architecture Roles	The distinct scopes of architecture practice — enterprise, solution, domain and application — and the different skills and decision rights each carries.
Architect Career Path	concept	Career Development	The progression from technical depth through breadth to organisational effect, and the skill shifts each stage requires.
Architectural Debt	concept	Evolutionary Architecture	Structural compromises that increase the cost of all future change, distinguished from code-level debt by being expensive and slow to repay.
Architectural Driver	concept	Architecture Fundamentals	The small subset of requirements and constraints that actually shape the structure of the system.
Architectural Significance Architecturally Significant Decision, Significance Test	concept	Software Architecture	The test that separates decisions worth reviewing from the ones a team should make alone, by asking what undoing each one would cost rather than how technical it sounds.
Architecture Development Method	concept	TOGAF	TOGAF's iterative cycle for developing enterprise architecture, which is valuable as a checklist of concerns and harmful when followed literally.
Architecture Governance Model	concept	Architecture Governance	The definition of which architectural decisions require which level of scrutiny, and who holds the authority for each.
Architecture Sinkhole	concept	Layered Architecture	A request that passes through every layer of a layered architecture without any layer adding logic, indicating that the layering is pure overhead for that path.
Architecture Style	concept	Architecture Styles	A system-level organising shape — layered, modular monolith, service-based, microservices, event-driven, space-based — chosen for the properties it makes cheap.
Architecture Style	concept	Architecture Fundamentals	A named, coarse-grained way of organising a whole system, as distinct from a pattern that solves one recurring problem inside it.
Architecture Viewpoint	concept	Architecture Documentation	A perspective on a system tailored to the concerns of a particular audience, recognising that no single diagram serves everyone.
Arrival Rate Model	concept	Performance Test Design	Driving a load test by requests arriving per second regardless of how the system responds, rather than by a fixed number of virtual users.
Assertion Strength What Coverage Does Not Measure, Mutation Score	concept	Mutation Testing	Whether a test would actually fail if the code were wrong - which coverage does not measure and mutation testing does, and which explains defects in fully-covered code.
Assurance and Governance	concept	Assurance, Audit & Model Risk	Providing confidence that controls exist and operate — through automation and evidence rather than through review meetings.
At-Least-Once Delivery Redelivery Semantics, Duplicate-Tolerant Delivery	concept	Webhooks	The delivery guarantee that a message will arrive but may arrive more than once - the strongest practical guarantee across an unreliable boundary, which pushes the deduplication responsibility onto the receiver.
Atomic Commit Protocol	concept	Distributed Transactions	Any protocol ensuring that several participants reach the same decision to commit or abort — and a problem provably unsolvable with certainty in an asynchronous system with failures.
Attack Surface	concept	Threat Modelling	The complete set of points where an untrusted actor can interact with a system — and the quantity that reduction genuinely reduces risk.
Attestation Freshness Nonce-Bound Quote, Replay-Resistant Attestation	concept	Edge Security & Attestation	The property that a hardware attestation can only be used in the exchange that requested it - without which a captured measurement is a reusable bearer token for the whole fleet.
Attribute History Strategy	concept	Slowly Changing Dimensions	The per-attribute decision about whether history is overwritten, versioned or kept alongside the current value, which is a business question rather than a technical one.
Audit Evidence	concept	Audit Evidence	Durable, tamper-resistant records demonstrating that a control operated as described, for every instance in the period under review.
Auditability	concept	Security Architecture	The ability to reconstruct who did what, to which resource, when, and from where — reliably enough to be relied upon after the fact.
Authentication AuthN	concept	Security Architecture	Establishing who a principal is, to a defined level of confidence.
Authorization AuthZ	concept	Security Architecture	Deciding whether an authenticated principal may perform a specific action on a specific resource.
Automation Bias Deference to Automation, Rubber-Stamp Oversight	concept	Human-in-the-Loop Design	The well-documented tendency for people to defer to a system's output rather than assess it independently - which is why nominal human oversight provides no protection.
Automation Ratchet Residual Difficulty, Hard-Case Concentration	concept	Human in the Loop	The effect where improving automation makes the cases reaching humans systematically harder, so reviewer throughput falls and error rates rise even as the overall system improves.
Availability Arithmetic	concept	Availability Mathematics	Multiplying dependency availabilities in series and combining redundant components in parallel to derive a system's achievable availability.
Availability Calculation	concept	Reliability & Resilience	Deriving a system's availability from its components, remembering that dependencies in series multiply.
Availability Composition	concept	Availability Mathematics	How the availability of a system follows from its dependencies — multiplying for serial dependencies and improving sharply for redundant ones.
Availability Zone AZ	concept	Cloud Architecture	One or more physically separate data centres inside a cloud region, with independent power, cooling and network, connected by low-latency links.
Availability Zone Independence	concept	Availability Zones	The property that a failure in one zone does not propagate to another, and the design work needed to actually benefit from it.
Background Work on Mobile	concept	Push & Background Work	Work scheduled outside the foreground session, which mobile operating systems aggressively restrict to protect battery life.
Backpressure	concept	Distributed Systems	A mechanism by which a component under load tells its callers to slow down, rather than accepting work it cannot complete.
Backpressure in Streaming	concept	Streaming & Real-Time Data	A slow downstream stage signalling upstream to slow down, so that queues stay bounded instead of consuming memory until the job dies.
Backward Compatibility	concept	API & Integration	The property that a new version of a producer continues to work with clients written against the old version.
Bake Time	concept	Multi-Region Rollout	The deliberate wait between rollout steps, sized by how long the fault you are watching for takes to appear.
Bandwidth-Delay Product	concept	Network Performance	Bandwidth multiplied by round-trip time — the amount of data that must be in flight to keep a link fully utilised.
Batch Orchestration Workflow Orchestration, DAG Scheduling	concept	Batch Orchestration	Running interdependent data jobs in the right order with retries, backfills and failure handling, expressed as a dependency graph rather than a schedule.