fricative

A *fricative* is a sound that you make by making friction in your mouth. The friction in the sound is caused by narrowing the airway. It is a sound that you can make continuously. Say the sound "s" in English. Now say this--"sssssssss." You can make that sound without moving or opening your mouth. Now try "sh." Can you make that sound continuously? Yes, you can. That's another fricative. But let's try a sound that is not a fricative in English. Let's try one of our *stops*--"b." Can you make this sound "bbbbbbbb" without moving or opening your mouth? No, you can't. It sounds more like "bebebebebe." That is because it is not a fricative, it is a stop. There is friction in the sound caused by narrowing the airway.