1.
A ~ is a map that shows the main roads in a particular area or the main routes used by buses, trains and other forms of transport in a particular area.
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2.
If you describe one thing as a ~ for another thing, you mean that it provides a model showing the best way to achieve or describe it.
Nowhere could you find a better ~ of the troubles of Northern Ireland than in the articles of The Independent’s David McKittrick.
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