{"schema":"chessgrammar_motif_entry/1","slug":"hanging-piece","name":"Hanging Piece","aka":"undefended piece · free piece","category":{"key":"constraint","label":"States"},"edition":{"version":"v3.0","year":"2026"},"certified":true,"canonical":"https://chessgrammar.com/motifs/tactics/hanging-piece","tabs":{"identity":"https://chessgrammar.com/motifs/tactics/hanging-piece#identity","structure":"https://chessgrammar.com/motifs/tactics/hanging-piece#structure","examples":"https://chessgrammar.com/motifs/tactics/hanging-piece#examples"},"citation":"ChessGrammar (2026). Hanging Piece. In: ChessGrammar: A reference for chess concepts, Tactics grammar, edition v3.0. Entry cg:hanging_piece@1. https://chessgrammar.com/motifs/tactics/hanging-piece","variants":["bishop","king_adjacent","knight","pawn","queen","rook"],"seeAlso":["fork","deflection","trapped-piece"],"definition":{"id":"cg:hanging_piece@1","statement":"A piece other than the king is attacked by a legal capture and has no legal recapture defending it.","predicate":["The piece is not the king. At least one enemy piece can legally capture it, and no friendly piece can legally recapture on that square. Both counts use only legal captures, and geometric attacks alone do not count. An attacker that is absolutely pinned does not count, because its capture would be illegal. A defender whose recapture would leave its own king in check does not count either.","There is no material threshold and no comparison of values. An undefended pawn that is attacked is hanging exactly as a queen would be. The neighbouring case is a piece that is en prise but still defended, perhaps attacked by a piece worth less. That piece is not hanging.","The piece was not already hanging before the move was played. The motif marks pieces that have just become vulnerable. The gain must also be realisable. On the next move, taking the piece must be a legal and profitable capture for the attacking side, and a geometric threat alone is not enough. The side that owns the piece must also be unable to end the threat without losing material, for example by capturing the attacker when nothing recaptures."],"diagnosis":"Its nearest neighbour is a piece en prise that is still defended, perhaps attacked by a piece worth less. The difference between the two is whether a legal defender exists. It never depends on a comparison of values.","maturity":{"state":"stable"},"holotype":{"fen":"6k1/1n6/8/8/8/8/6PP/R5K1 w - - 0 1","move":"a1b1","san":"Rb1","hanging":"b7","attacker":"b1","defenders":[],"why":"White plays Rb1 and newly attacks the undefended black knight on b7 along the open b-file. Before the move, the rook stood on a1, off that file, so b7 was not attacked at all. The knight is newly hanging. No black piece defends b7, and the king on g8 is five squares away. Rxb7 wins the knight outright."},"nearMiss":{"fen":"2k5/1n6/8/8/8/8/6PP/R5K1 w - - 0 1","move":"a1b1","san":"Rb1","hanging":"b7","attacker":"b1","defenders":["c8"],"delta":"The black king stands on c8 instead of g8, adjacent to b7. Only one square of the position changes.","neighbour":"none","why":"Only the king's square has changed. From c8 the king is adjacent to b7, and after Rxb7 no other white piece attacks b7. Kxb7 is legal, so b7 is defended after all. The piece is not hanging, and no sibling entry covers this position."},"nearMissPending":null,"standing":{"certified":true,"scope":"definition"}},"axes":[{"key":"piece","name":"The nature of the hanging piece, or its adjacency to its own king","values":["bishop","king_adjacent","knight","pawn","queen","rook"],"nature":"facts","exclusive":[["bishop","knight","pawn","queen","rook"]],"note":"Five values (bishop, knight, pawn, queen, rook) partition by piece type -- mutually exclusive by construction, since a piece has exactly one type. The king-adjacent value is not a sixth type: it is a separate positional fact (the piece stands one square from its own king) that co-fires alongside whichever type value applies."}],"summary":"A piece under attack with no legal defender, so it can be won at once."}