A buzzword is a word or phrase that is made to either summarize a complex idea or reconstruct another word or phrase to reflect a particular point of view. Corporations make up buzzwords so that they can advertise stuff better. In this way, a buzzword is a lot like a product name or a proper noun. People can remember buzzwords better than non-buzzwords, which is why its good for advertising.
Example: Multimedia has been a buzzword in the computer industry for years.