(~s)
1.
A ~ is a place, usually underground, that has been built with strong walls to protect it against heavy gunfire and bombing.
...an extensive network of fortified underground ~s.
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2.
A ~ is a container for coal or other fuel.
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3.
On a golf course, a ~ is a large area filled with sand, which is deliberately put there as an obstacle that golfers must try to avoid.
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