1. To cover the king with a castle, by a certain move. Castle in the air, a visionary project.

2. A fortified house or fortress; the mansion of a nobleman or prince.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• wistle,
• pastle,
• castals,
• catle,
• crystle,
• castal,
• casll,
• caslte,
• casette,
• lastley,
• caslt,
• casade,
• casttles,
• castl,
• casel,
• chastle,
• casltle,
• castel,
• rascle,
• casta

• castle-building,
• castelao,
• costly,
• casteel,
• cattle,
• Costal-nerved,
• castile-la,
• castella,
• castello,
• kastella,
• Castelli,
• Infra-Costal,
• castaldi,
• Castle-builder,
• castell-rudenhausen,
• gustily,
• gestell,
• Castle-ward,
• kostal,
• jostle,
• coastline,
• kostel,
• castilho,
• kastel,
• castilleia,
• Gastly,
• costley,
• costlier,
• CSDLA,
• coastal,
• castling,
• stern-costal,
• GASTEL,
• costalia,
• castle-air,
• CASTL,
• castle-buildings,
• castelo,
• castle-builders,
• castellia,
• Costello,
• costally,
• castle-like,
• castell,
• castaldo,
• custalow,
• castil-blaze,
• quistelli,
• gestel,
• Castle-guard,
• casteless,
• castiel,
• castellon,
• un-costly,
• CASTEL,
• khuzdul,
• GST1L,
• ghostley,
• castil,
• kastelli,
• castillon,
• ghostly,
• less-costly,
• faber-castell,
• Castalia,
• pastel,
• castille,
• Castallia,
• cast,
• union-castle,
• guastella,
• kastle,
• gastelli,
• Castillo,
• kasteel,
• Costlewe,
• gausdal,
• castleman,
• CSDHL,
• Castlen,
• Quesadilla,
• CSTyL,
• Kastalia,
• costal,
• costel,
• coastally,
• castled,
• castile,
• CCSTL,
• ghastly,
• gwizdala,
• castilla,
• ghastlier,
• gestal,
• cussedly,
• kastl,
• questel,
• costelloe,
• guastalla,
• costilla,
• ghostlier.

The adjective form of the word "castle" is "castellated".

The plural of the "castle" can be the "castles".

The singular of the "castle" can be the "castle".