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    1. ballast

      英 ['b?l?st] 美['b?l?st]
      • n. 壓艙物,[建] 壓載物;道渣,碎石
      • vt. 給…裝壓艙物;給…鋪道渣

      英英釋意


      1. any heavy material used to stabilize a ship or airship
      2. coarse gravel laid to form a bed for streets and railroads
      3. an attribute that tends to give stability in character and morals; something that steadies the mind or feelings
      4. a resistor inserted into a circuit to compensate for changes (as those arising from temperature fluctuations)
      5. an electrical device for starting and regulating fluorescent and discharge lamps