A large residential building or compound that is fortified and contains many defences; in previous ages often inhabited by a nobleman or king. Also, a house or mansion with some of the architectural features of medieval castles.

(transitive) To house or keep in a castle. / (transitive, figuratively) To protect or separate in a similar way.

plural of castle

Third-person singular simple present indicative form of castle

simple past tense and past participle of castle

Furnished with castles.

(countable) A surname transferred from the common noun referring to someone who lived in or worked in a castle / (UK, rail transport) Castle class, a class of steam locomotives used on the GWR

plural of castleful

Enough to fill a castle.

(obsolete) An abortion, or a premature birth. / (obsolete) The second or third swarm of bees which leaves a hive in a season. / A miniature cast or mould. / One that is cast.