Glossary

Defined terms used throughout the specification. Where a term is defined in detail in a chapter, that chapter is linked.

This page is not normative on its own — the linked chapter is the source of truth — but implementations and authors SHOULD use these exact spellings. The vocabulary is closed by design (principles P3); inventing parallel terminology defeats the lint loop.

Architecture and IR

• Block-array IR. The universal pivot at the bottom of the three-layer IR: a voxel grid + palette + block entities + entities, neutral to format, edition, and version. Every format’s frontend/backend, plus diff/IoU/serialization, meet here. See architecture §3.1.
• Intent IR. The top layer: named members carrying id / class / role / mat_slot / intent_state / resolved_state. Independent type with invariants; not produced directly by schematic ingestion. See architecture §3.2.
• Semantic / Component-Theme IR. The middle layer that resolves themes, components (def), and multi-building (site) into the Intent IR. See components-editing-sites, materials-themes.
• Logic IR / Netlist IR / Placement IR. The three redstone sub-layers between Intent IR and block-array IR. Delay is not carried in Logic/Netlist — only the Placement IR has it. See redstone §14.8, architecture §3.3.
• semantic_level. An imported artifact’s progress label: raw (one voxel per line) → grouped (L1 spatial compression) → lifted (L2 semantic naming). The compiler reaches L1; L2 is the LLM’s job. See ecosystem-interop §12.3.

Members and blockstate

• Member. A named element of the Intent IR. Types: block, block_entity, entity. The IR carries the type, but the author writes one selector grammar across all of them (principles P4).
• id / class / role. Identity, group, and architectural function tags on a member. Used for selectors and stable addresses.
• mat_slot. A material injection point on a member; bound by a theme. Structure carries slots, themes carry block bindings. See materials-themes §7.1.
• intent_state. The author’s blockstate intent. Edit diffs look only here. See blockstate §6.2.
• resolved_state. Compiler-derived blockstate (orientation, connections, waterlogged). Never hand-written.
• Override-promotion. Writing a blockstate that could be intent promotes it from resolved_state to intent_state. The spec rule is “derive by default; any blockstate that can be intent is overridable.” See blockstate §6.1.
• Anchor / bbox. Every primitive carries an anchor (reference point), a declared bbox, an actual bbox, and a host face in the IR — needed because primitives like paintings, item frames, and arch windows have a declared size that differs from the occupied AABB. See entities §8.2.

Materials and themes

• Canonical token. The value bound to a slot or theme selector: a meaning token, not a raw block ID. The backend resolves the per-(edition, version) ID and state names. See materials-themes §7.2.
• Canonical block token. A specific block meaning: @oak_planks, @water_cauldron, @oak_log[axis=x]. Silent meaning-breaking downgrades (@water_cauldron → cauldron) are forbidden.
• Abstract material token. An aesthetic choice: @floor.wood.broadleaf, @roof.dark_wood. Theme policy MAY downgrade these (e.g. oak↔birch).
• theme. A CSS-like binding of slot/selector values to canonical tokens. Separates structure (where the walls are) from style (which blocks).
• def. A slot-bearing Component definition (a reusable struct). Recursion forbidden; parameterization allowed. The minimum version of a composite is the max of its parts. See components-editing-sites §9.1.
• site. A multi-building container that places def-derived structures by topological relations (east_of, gap=, connect), not absolute coordinates. See components-editing-sites §9.3.

Compilation

• Phase. A fixed evaluation slot the compiler sorts each command into: massing → envelope → openings → fixtures → logic_synth → logic_place → logic_route → raw. Source order is irrelevant; phases enforce semantics (compilation §4.1).
• Last-wins (local). Within the same phase, a later command overrides an earlier one. The old whole-program last-wins (“paint model”) is dropped. See principles P2.
• Target axes. (edition, version): the only layer that knows them is the backend. The DSL source never names them. --edition is required, --target alone is forbidden. See compilation §4.2, versioning-editions.
• DataVersion. Mojang’s monotonically increasing integer key for a Java version. Cairn uses it as the canonical ordering key so the semver→date-based version transition does not break since/until or @requires. See versioning-editions §10.1.

Headers and provenance

• @cairn. Header declaring the Cairn language version the file was written against (CalVer YYYY.0M[.PATCH]). Provenance only; optional.
• @requires. A capability floor on the Minecraft target (e.g. version>=1.20). Hard error on conflict with the inferred value.
• @intended_targets. A hint about which Minecraft versions the file was designed for. Not a verification record — the record lives in the lock.
• Lock (*.cairn.lock). Compiler-generated reproducibility record. Carries source_hash, cairn_version, target(mc_version + data_version), registry_pack_hash, constraint_catalog_hash, resolved_ir_hash, and verified: true. See versioning-editions §10.6.
• Provenance stamp. (edition, version) recorded onto the block-array IR on import, mapped from the format itself (.litematic → java, .mcstructure → bedrock, .schem → java). See ecosystem-interop §12.4.

Redstone

• Logical cell / edition cell / physical tile. The three-tier cell library. The Logic IR selects logical cells; the per-edition cell library lowers them to physical tiles. Confines the Java/Bedrock difference to the library. See redstone §14.6.
• Combinational vs sequential. v1 ships closed-set combinational gates and curated sequential macros (latch / pulse / delay / edge_rising / edge_falling / counter). Arbitrary FSMs / CPUs are out of scope for v1.
• Truth / latency / temporal assertion. The three verification kinds. See redstone §14.7. Temporal is bounded eventually within N only, not full LTL.
• QC / BUD. Quasi-connectivity / block-update-detector behaviors. Not absorbed by the cell library; a circuit that depends on update-order semantics is an E_NO_PORTABLE_IMPL compile error.

Lint and evaluation

• Self-correction loop. The compile → diagnostics → patch → recompile cycle that lifts precision out of one-shot generation (principles P5). Diagnostic messages MUST be in “what is wrong / valid candidates in the target / suggested fix” form (lint).
• Fail-loud. Silent substitution and implicit dropping of unknown IDs / out-of-domain states are forbidden. Errors return the closed set of valid candidates plus a suggested DSL fix. See versioning-editions §10.4.
• semantic_sensitivity. A constraint-catalog field distinguishing “the ID stays valid but meaning/behavior/appearance changed at this version” from since/until. Cauldron split @1.17, wall connection bool→none/low/tall @1.16, item format @1.20.5 are examples. See versioning-editions §10.5.
• Block IoU. Voxel intersection-over-union used for the import self-correction loop. Convergence threshold ≥ 0.985. See ecosystem-interop §12.2, evaluation §13.2.
• Zero-shot Compile Rate / Fix Convergence Rate / Token Efficiency / Edit Stability. The four primary spec-iteration metrics. See evaluation §13.1.

Editions and versions

• Edition. java or bedrock. Compile-time only; never present in the DSL semantic layer. See versioning-editions §10.7.
• Cairn version vs MC target. Two separate axes distinguished by field/flag/keyword, never by format. cairn:2026.06 vs mc:1.21.4 in disambiguating prose. See Specification overview, versioning-editions.
• Recompile, don’t transcode. The language spec does not guarantee NBT portability across version or edition. To target a new version, recompile the DSL; do not convert the NBT. See versioning-editions §10.2.

Ecosystem interop

• Raw / L1 / L2. The three tiers of faithful transliteration on import. The compiler reaches L1 (spatial compression, no naming); L2 is the LLM’s job (naming → wall, mat_slot, theme). See ecosystem-interop §12.3.
• raw_fill / raw_block / raw_repeat. Escape-hatch primitives used by faithful transliteration. Import-origin instances carry origin=imported so they are not treated as first-class design DSL.