2. Any of various submarine explosive devices; especially, a submarine mine: "The navy administration admitted to having an excess stock of torpedoes at the naval base."
3. A small explosive placed on a railroad track which is fired by the weight of the train to sound a warning to the engineer of an approaching hazard or danger ahead: "The train-track maintenance crew placed a small torpedo on the track to warn the engineer of the train to slow down at the bridge crossing."
4. An explosive fired in an oil or gas well to begin or to increase the flow the oil or gas: "The use of torpedoes in oil or gas fields requires significant safety planning."
5. A small firework consisting of gravel wrapped in tissue paper with a percussion cap that explodes when thrown against a hard surface: "The youth enjoyed throwing the torpedoes on to the hard pavement of the street during the holiday celebrations and watching them explode."
6. Etymology: from the 1520's, "electric ray", from Latin torpedo; originally, "numbness" (from the effect of being jolted by the ray's electric discharges), from torpere, "to be numb".
From New Latin Torpedo, a genus of fish which give electric shocks, which came from Latin torpedo, "stiffness, numbness, the torpedo" (fish), from torpere, "to be stiff".
The sense of "an explosive device used to blow up enemy ships" was first recorded in 1776, as a floating mine; the "self-propelled" version came from the 1860's.
2. To spoil, to undermine, to ruin, or to destroy something completely: "The union threatened to torpedo the agreement unless the company agreed to make retroactive pay increases."
"To explode a torpedo in an oil or gas well facilitates the extraction of such elements."