Terminology

2205 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 areas2205 Architecture Fundamentals77 Distributed Systems107 Data Architecture110 Cloud Architecture94 Networking88 API & Integration Architecture82 Reliability & Resilience75 Observability70 Performance & Capacity Engineering72 Security Architecture86 Cost Architecture & FinOps71 Business Architecture67 Architecture Communication67 Enterprise Architecture66 Legacy Modernization71 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 concept794 practice734 pattern368 metric125 case-study77 tool62 protocol45

734 terms shown.

Term	Kind	Topic	What it is
Cost Allocation Tagging	practice	Cost Allocation	A mandatory, enforced tagging scheme that attributes every resource to an owner, so spend can be understood and acted on below the level of the whole account.
Cost Attribution Tagging Strategy, Cost Ownership	practice	Cost Allocation	Assigning every unit of infrastructure spend to a team and a product, enforced at resource creation - the prerequisite without which no other cost control works.
Cost Governance	practice	Cost Governance	The guardrails, budgets and approval structures that prevent cost surprises without becoming a bottleneck.
Cost Model Sensitivity	practice	Architecture Cost Modelling	Identifying which assumptions in a cost projection dominate the outcome, so effort goes into the estimates that actually matter.
Cost of Inaction Cost of Delay, Do-Nothing Cost	practice	Business Cases	The quantified ongoing cost of leaving a system as it is - the number that lets architectural work compete against feature work for funding.
Counterfactual Structure Test Driver Test, Would-The-Shape-Change Test	practice	Architectural Drivers	The one-question test that separates architectural drivers from important features - remove this requirement, and would the structure of the system change?
Critical Path Analysis Span Critical Path, Blocking Time Analysis	practice	Distributed Tracing	Identifying which spans in a trace actually block the response, as opposed to running in parallel, so optimisation effort targets the work that determines latency rather than the work that merely appears slow.
Cross-Service Debugging	practice	Debugging Distributed Systems	Investigating a failure that spans multiple services by moving between traces, logs, metrics and profiles along a single correlated request.
Crypto-Shredding Cryptographic Erasure	practice	Data Lifecycle & Retention	Making data permanently unreadable by destroying its encryption key, so immutable copies in backups and archives are erased without being modified.
Cursor Pagination Keyset Pagination, Seek Pagination	practice	Pagination & Filtering	Paginating by encoding a position in a stable sort order rather than by numeric offset - constant cost per page and correct under concurrent modification.
Cutover Abort Criteria Stop Conditions, Numeric No-Go Thresholds	practice	Migration Risk	Numeric thresholds agreed before a cutover with one named person empowered to apply them, which replaces an improvised 03:00 judgement made by the people with the most sunk cost in continuing.
Cutover Planning	practice	Cutover Planning	The plan for the moment of switching — including the decision points, the rollback, and the rehearsal that makes it survivable.
Cutover Runbook	practice	Cutover Planning	The step-by-step plan for a migration event, including verification points, decision criteria and the rollback path, rehearsed before it is used.
Dark Failover Shadow Failover, Non-Serving Failover Rehearsal	practice	DR Testing	Bringing a standby environment to full serving readiness and exercising it with synthetic or internal traffic while production continues untouched, so recovery is measured without an outage being risked.
Dashboard Hierarchy	practice	Dashboards	Organising dashboards into service-level, diagnostic and deep-dive layers so each answers a specific question at a specific moment.
Dashboards	practice	Dashboards	Curated views built for a specific question — with the failure mode of showing everything and answering nothing.
Data Discovery	practice	Data Classification	Automatically scanning stores to find where sensitive data actually resides, as distinct from where the documentation says it should.
Data Flow Diagrams	practice	Data-Flow Diagrams	Where data goes, who holds it and which boundaries it crosses — the artefact that answers privacy, residency and threat-modelling questions.
Data Governance	practice	Data Governance	Making data ownership, meaning, quality and access explicit — the mechanism that keeps a data platform trustworthy as it grows.
Data Key Caching Key Reuse Window, Envelope Key Caching	practice	Key Management	Reusing one generated data key across a bounded number of objects, bytes and seconds, so that envelope encryption does not make one key-service request per record.
Data Lifecycle	practice	Data Lifecycle & Retention	Managing data from creation through tiering to deletion — the discipline that keeps storage cost and legal exposure bounded.
Data Lineage	practice	Data Governance	A record of where each dataset came from, what transformed it, and what depends on it — traced at table and ideally column level.
Data Migration Strategies	practice	Data Migration Strategies	Moving data between systems with different models — where the difficulty is meaning and quality rather than transfer.
Data Observability	practice	Data Observability	Continuous automated monitoring of data health — freshness, volume, schema, distribution and lineage — designed to detect silent data failures.
Data Retention Policy	practice	Data Architecture	A defined rule for how long each class of data is kept, where, and what happens at the end of it.
Data-Flow Diagram DFD	practice	Architecture Communication	A diagram of how data moves between processes, stores and external entities, with trust boundaries drawn on it.
Database Migration	practice	Database Migration	Moving data from one store to another while the system keeps running — where verification and reversibility matter more than the copy itself.
Database Migration Strategy	practice	Database Migration	The approach for moving data to a new store, which is usually the longest pole and the highest risk in any modernisation.
Database Performance	practice	Database Performance	The interventions that resolve database bottlenecks, in the order they should be attempted.
Dataset Deprecation Policy Dataset Sunset Policy, Retirement Notice Period	practice	Data Products	The written rule stating how a published dataset or column is retired - the notice period, how consumers are identified, and what happens if they do not move - without which nothing can ever be removed.
Dataset Ownership Boundary Data Product Boundary, Published Dataset Surface	practice	Data Platform Architecture	The line between a producing team's internal data and the surface it publishes - which is what makes decentralised data ownership safe rather than fragmenting.
Debt Register	practice	Technical Debt	A maintained record of known technical compromises with their cost, impact and repayment trigger, making debt manageable rather than merely felt.
Debugging Distributed Systems	practice	Debugging Distributed Systems	A method for diagnosing failures whose cause is in a different service from the symptom.
Decision Context Capture	practice	Architecture Decision Records	Recording the situation, constraints and forces that made a decision reasonable, so that later readers can judge whether it still applies.
Decision Granularity One Decision Per Record, Record Scope	practice	Architecture Decision Records	How much a single decision record covers, chosen so a later change can replace exactly the part that has become wrong instead of invalidating a document that is mostly still correct.
Decision Narrative	practice	Writing Decision Records	Writing a decision record so that the reasoning survives the author, focusing on the forces and the rejected options rather than the conclusion.
Decision Restatement Implementer Read-Back, Assent by Restatement	practice	Presenting to Engineers	Requiring the people who will implement a decision to write back what they will build and why, so that agreement is demonstrated by the receiver rather than inferred from an approval click.
Decision Rights Decision Ownership, Accountable Decider	practice	Architecture Decision-Making	An explicit statement of who decides what, so that consultation is bounded and decisions do not wait for a consensus nobody required.
Decision Trigger Revisit Condition, Pre-Agreed Threshold	practice	Managed vs Self-Managed	A number or condition agreed in advance that would cause a decision to be revisited - which converts a permanent choice into a monitored one and prevents both premature change and indefinite drift.
Decision Under Uncertainty	practice	Deciding Under Uncertainty	Choosing when the information needed to be confident is unavailable, using the cost of being wrong rather than waiting for certainty.
Decision-Forcing Proposal	practice	Technical Proposals	A written proposal structured so that deferring is visibly a choice with a cost, rather than a free default.
Decision-Making Under Uncertainty	practice	Meta-Skills	Choosing well when the information is incomplete — by bounding the downside and buying information, rather than by waiting for certainty.
Decommissioning	practice	Decommissioning	Actually switching off and removing a replaced system, which is where the savings in every modernisation business case live.
Decommissioning Discipline	practice	Decommissioning	The work of actually switching a legacy system off, which is where migration savings are realised and which is routinely left undone.
Decomposition by Capability	practice	Application Decomposition	Breaking a monolithic system into parts along business capability lines rather than technical layers, so that each part changes for one reason.
Default Deny	practice	Firewalls & Security Groups	A firewall posture in which nothing is permitted unless explicitly allowed, as opposed to blocking known-bad traffic.
Definition of Done	practice	Quality Gates	The agreed, explicit conditions under which work is finished, which functions as a quality gate only when it is automated and non-negotiable.
Degradation Ladder Kill Switch List, Feature Shedding Order, Brownout Plan	practice	Degradation Modes	An ordered, pre-agreed list of features that can be disabled under stress, each with a switch that works without deployment, a named owner, a trigger condition and a rehearsed fallback.
Degradation Ladder	practice	Architecture Roles	A pre-agreed ordered list of capabilities the system sheds under load, with the ordering owned by the business and the mechanism owned by the architect.
Deletion Safety Threshold Mass-Delete Guard, Sync Blast Radius Limit	practice	Partner & B2B Integration	A refusal to process a deletion batch above some proportion of the population without human confirmation - the control whose absence produces the most damaging incidents in synchronisation systems.
Deletion Verification	practice	Retention & Purge	Proving that a deletion actually removed the data everywhere it existed, which is a harder problem than issuing the delete.
Deliberate Technical Debt	practice	Delivery vs Maintainability	A consciously chosen shortcut, recorded with its cost and a repayment trigger, as distinct from debt incurred by carelessness.
Delivery Attempt Log Webhook Delivery History	practice	Webhooks	A customer-visible record of every outbound delivery attempt - its response, timing and payload - which converts a support burden into self-service.
Delivery Pipelines	practice	Delivery & Release Engineering	The automated path from commit to production — where speed and trustworthiness determine whether anyone uses the feedback it produces.
Demand Forecasting	practice	Capacity Modelling	Projecting future load from historical trends, business plans and known events, and translating it into resource requirements with explicit lead times.
Denormalisation	practice	Data Architecture	Deliberately duplicating data across records to make reads cheap, accepting the write-time cost of keeping copies in step.
Dependency Reproducibility Same Commit Same Dependencies, Pinned Builds	practice	Build Reproducibility	Guaranteeing that a given commit pulls the same dependencies every time - the practical subset of build reproducibility that delivers most of its value for a fraction of the effort.
Deployability Test Can You Deploy Alone, Boundary Justification Test	practice	Microservices	Asking whether one team can change, deploy and roll back a service without telling the others - the single test that distinguishes a boundary delivering independence from one delivering only cost.
Deployed-Artefact Assertion Fleet Version Assertion, Release State Check	practice	Testing in Production	A check run after every deployment that compares the build identifier reported by each running host against the intended release, so a partially applied deployment fails loudly instead of running two behaviour…
Deployment Compatibility Check Can-I-Deploy, Deployment Gate on Contracts	practice	Contract Testing at Scale	A pre-deployment query asking whether this version is compatible with everything currently deployed - which turns contract tests from a test into a release gate.