(~s)
1.
A ~ is a long narrow container from which farm animals drink or eat.
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2.
A ~ is a low area between two big waves on the sea.
The boat rolled heavily in the ~s between the waves.
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3.
A ~ is a low point in a process that has regular high and low points, for example a period in business when people do not produce as much as usual.
Looking back afterwards you will see that this was not a terminal ~ in your career...
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4.
A ~ of low pressure is a long narrow area of low air pressure between two areas of higher pressure. (TECHNICAL)
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