Modifies a noun

• motorist: But they are also on straight roads where arbitrary speed limits trap the unwary motorist when a higher speed may be perfectly safe.

• traveler: The sands are about 8 miles across, and are often fatal to unwary travelers.

• buyer: This can be a trap for the unwary buyer or seller.

• reader: I've added an X to the above links, so that they won't infect an unwary reader of this message.

• fish: Here they will lurk waiting to attack any unwary fish that ventures too close.

• user: The first contact is usually made through email, enticing the unwary user to an infected site.