Tarmac - UK English, blacktop - Am English.
Zakładam, że chodzi o budownictwo drogowe.

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Note added at 20 mins (2007-02-27 11:39:01 GMT)
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Ale może być również asphalt, ponieważ to słowo jest uzywane zarówno w odniesieniu do samego bitumenu jak i do takiej właśnie mieszanki

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Note added at 2 hrs (2007-02-27 14:10:43 GMT)
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Tarmac [4.1MG] refers to a material patented by E. Purnell Hooley in 1901. The term is also used, with varying degrees of correctness, for a variety of other materials, including tar-grouted macadam, Tarvia, bituminous surface treatments and even modern asphalt concrete.

2. Blacktop [1.7MG] may refer to asphalt concrete, a composite material commonly used for construction of pavement, highways and parking lots bituminous macadams, tarmac.

Patrz też poniższa uwaga A.G.

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Note added at 2 hrs (2007-02-27 14:11:22 GMT)
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