knight.head

n.Nautical （名詞）【航海】
Either of two timbers rising from the keel of a sailing ship and supporting the inner end of the bowsprit.
艏副肋材：兩根肋材中的任一根，從帆船的龍骨伸出并支撐船首斜桁內端

來源：
[From the fact that it was sometimes decorated with a carving of a man`s head]
[源自它有時被飾有男子頭像的事實]