dropper

noun

1. A utensil for dispensing a single drop of liquid at a time.

2. One who drops something, especially one who drops a specific item to cause mischief.

   The dropper left the suitcase with the bomb next to the garbage can.

3. A software component designed to install malware on a target system.

4. A fly that drops from the leaden above the bob or end fly.

5. A branch vein which drops off from, or leaves, the main lode.

6. A dog which suddenly drops upon the ground when it sights game.

7. A person who uses fraudulent cheques.