fut.tock

n.Nautical （名詞）【航?！?/i>
One of the curved timbers that forms a rib in the frame of a ship.
復肋材：構成船的肋骨部位的曲線形木材

來源：
Middle English fottek
中古英語 fottek
perhaps alteration of fothok
可能為 fothok的變化
fot [foot] * see foot
fot [（帆的）下緣] *參見 foot
hok [hook] * see hook
hok [ 鉤狀物，錨] *參見 hook