EditionAn identified version of the reference or its taxonomy to which a record belongs.Time and provenance
ElementA unit described by a grammar: a fact, relation, structure, action or other formal chess object.Grammar and objects
Escape squareA square the king could legally move to if it were attacked.Chess
ExchangeA capture answered by a recapture, weighed by the value of the pieces that leave the board.Chess
F
FileA vertical column of eight squares, lettered from the queenside to the kingside.Chess
Forced moveA move that is the only reply avoiding an immediate and decisive loss, or the only legal move.Chess
G
GainThe material a side ends up ahead after the sequence under study, against the opponent’s best defence.Chess
GoalIn the tactics domain, the regime for an action whose announced outcome must hold under best defence.Verification and certification
GrammarA system of definitions and relations stating which objects belong to a domain and under which conditions they can be established.Grammar and objects
I
InstrumentalIn the tactics domain, the regime for a move whose role is established within an already determined goal.Verification and certification
L
Legal moveA move that the rules allow in the position shown, which excludes any move that leaves the mover’s own king in check.Chess
LineA rank, a file or a diagonal, considered as the path along which a long-range piece moves or attacks.Chess
LossThe material a side ends up behind after the sequence under study, against the opponent’s best defence.Chess
M
MaterialThe pieces each side has on the board, weighed by their conventional values.Chess
MoveA player’s action in which a piece goes from one square to another, with any capture, promotion or castling attached by the rules.Chess
N
Near-missA negative witness that resembles the object but fails a defining condition.Map and catalogue
O
ObjectA formally defined element whose membership can be established from the conditions of its grammar.Grammar and objects
Open domainA domain in which some objects have an implementation and a publishable record.Map and catalogue
OpponentThe side that is not to move in the position shown.Chess
P
PieceAny of the sixteen units a side starts with, pawns and king included.Chess
PredicateThe formal condition a claim must satisfy to be testable.Grammar and objects
PromotionA pawn that reaches the last rank is replaced, on the same move, by a queen, rook, bishop or knight of its colour.Chess
ProvenanceThe information connecting a claim to its definition, witnesses, sources and edition.Time and provenance
R
RankA horizontal row of eight squares, numbered from the side of the player with the white pieces.Chess
RecallThe proportion of the expected instances in a control reference that the system reports.Verification and certification
RecordA public page that brings together an object’s definition, witnesses, status, provenance and limits.Map and catalogue
RegimeA first-level class that groups the objects of a grammar by the kind of claim they make.Verification and certification
RelationA formal link between several elements of a position.Grammar and objects
ReproducibilityThe ability to repeat the same protocol under the same conditions and obtain the same measurements.Time and provenance
Reserved domainA recognised place in the general map with no claim of implementation, certification or schedule.Map and catalogue
S
ScreenA piece standing on a line between a long-range attacker and another piece further along that line.Chess
SequenceThe moves played by both sides in turn from the position shown, over which a claim is read.Chess
Side to moveThe side whose turn it is in the position shown.Chess
SoundnessThe ability of an announced outcome to hold against the opposing replies defined by the protocol.Verification and certification
SquareOne of the sixty-four cells of the board.Chess
StandingThe public state of a record: certified, measured but not certified, detected or another status explicitly defined by the record.Verification and certification
StateIn the tactics domain, the regime for a fact that is established in a position and has no autonomous outcome under adversarial play.Verification and certification
T
Type positionA positive witness chosen to represent an object by satisfying all of its defining conditions.Map and catalogue
TacticA short forcing operation that gains material or mates, resolved within a few moves against best defence.Chess
TargetThe piece, square or outcome that a motif is aimed at.Chess
ThreatA move available to the side to move that would gain something if the opponent did not answer it.Chess
U
UndefendedSaid of a piece whose square is attacked by none of its own side’s pieces.Chess
V
ValueThe conventional weight of a piece, counted in pawn units.Chess
VariantA named form of an object that inherits the object’s identity and regime and does not automatically become a separate object.Map and catalogue
VerificationA test of a claim by a procedure that could contradict it.Verification and certification
W
WitnessA position or example that makes a claim testable.Map and catalogue