ballast
بررسی کلمه. • (1) تعریف: heavy material placed in the hold of a boat or ship to make it more stable. • (2) تعریف: heavy material placed in the car of a balloon to make it more stable. • (3) تعریف: gravel or crushed rock under the rails and ties of a railway to increase stability. • : تعریف: to provide with ...