バラスト

noun

ballast (for ships, submarines, balloons)

Used for weight added to stabilize a vessel or aircraft, such as water in submarine tanks or sandbags in a hot-air balloon.

• 潜せん水すい艦かんはバラストタンクに水みずを入いれて潜せん行こうする。

  The submarine submerges by taking water into its ballast tanks.

• 熱ねつ気き球きゅうはバラストを捨すてて上じょう昇しょうした。

  The hot-air balloon ascended by dropping ballast.

noun

ballast (for road or railway foundations)

Refers to the layer of gravel or crushed stone placed under railway tracks or road surfaces to provide stability and drainage.

• 線せん路ろのバラストは定てい期き的てきに交こう換かんが必ひつ要ようだ。

  The ballast on the railway track needs to be replaced periodically.