A driftnet is a long fishing net that hangs in the water like a wall and floats along with the sea, often trailing behind a boat. The boat does not always drag it hard through the water; the net drifts, and fish swim into the mesh and get caught. People also write it as two words, drift net. It can be huge — far longer than the nets you see on a small harbour boat. Though actually, the word now often comes with an argument. A driftnet does not choose. Dolphins, turtles, sharks, and sea birds can get stuck and die too, so news and fishing law talk about banning the biggest ones. You will meet it in reports about the sea more than in kitchen talk.