Advertising or publicity that discredits a competitor's product.
贬低竞争者产品的广告（或宣传）
Example sentencesExamples
I can't imagine this type of knocking copy working particularly well, however.
The knocking copy won't put him off, but it would be nice if politicians and even the Fourth Estate realised that what he can do for Scotland is more important than whether he scowled or even growled at a reporter.
It's dead easy to write knocking copy as illustrated by his appallingly one-sided piece in the paper on December 31.
If you are expecting knocking copy about Radio Scotland, you won't get it from me,’ said Docherty.
In the UK no one did knocking copy until very recently.