1 a wasting away of the body, as from poor nutrition, nerve damage, or disuse. 2  to undergo atrophy; wither; degenerate:His crippled leg began to atrophy with no exercise. 3  to become weakened; decline:Industry atrophied in bad economic times.
Voice Amplifiers / Long Range Listening Devices. Listening devices can be utilized for a variety of purposes including listening through a wall, listening from a distance or enjoying your favorite animals in the wild. More complex systems contain an audio transmitter and receiver.
The transmission of signals over a distance for the purpose of communication began thousands of years ago. Early methods of long-distance communication included runners to carry important messages, smoke signals, chains of searchlights, drums, carrier pigeons, the Pony Express and the telegraph.