1. the practice or science of sending messages over long distances using electrical signals transmitted through wires or radio waves
2. the system or equipment used for transmitting telegraph messages

Examples

• The invention of telegraphy revolutionized long-distance communication in the 19th century.
• Samuel Morse played a key role in developing telegraphy in America.
• Before the telephone, telegraphy was the fastest way to send messages across continents.
• The transatlantic cable made telegraphy possible between Europe and North America.
• Wireless telegraphy preceded modern radio communication.
• Military forces relied heavily on telegraphy during wartime.
• The decline of telegraphy began with the widespread adoption of the telephone.