I was hoping to be the first, but will gladly be a followup to drpaladin. His responses were as usual, sharp and to the point. I have merely added some filler and fleshed them out a bit(taken from the reference that I found).

Tantivy is an adverb as well as a noun that refers to a rapid gallop. Although its precise origin isn't known, one theory has it that tantivy represents the sound of a galloping horse’s hooves. The noun does double duty as a word meaning "the blare of a trumpet or horn." This is probably due to confusion with tantara, a word for the sound of a trumpet that came about as an imitation of that sound. Both tantivy and tantara were used during foxhunts; in the heat of the chase, people may have jumbled the two.

Tantivy Definition & Meaning - Merriam-Webster

Tally Ho,

The OED says the earliest know use of the word was in 1681, in Heraclitus Ridens.  

In the 1930s, the US Navy thought its battles would be fought at long range, in the daylight, and torpedoes were obsolete. Japan trained and planned to fight at night at medium to short ranges, with fast, 30 foot torpedoes with a ton of explosives in their warhead. The Japanese Long-Lance (or Type 93) torpedo was developed by the Japanese in the thirties. Using liquid oxygen as a propellant, they were the fastest, longest ranged, and hardest hitting torpedoes in the world. (1) (2)

This cost the US dearly in the south Pacific in the early years of World War 2. US cruisers and destroyers often faced Japanese cruisers and destroyers armed with dozens of Long-Lance torpedoes tantivy closing the range to under 10,000 yards.

(1) Japanese Type 93 Torpedo

(2) Fubuki Class Destroyers (carry 9 Long-lance torpedoes in three mounts of 3 + reloads)

1 minute ago, drpaladin said:

The Type 93 was a devastating weapon under certain limited conditions, but faced with radar, powerful naval guns, and airpower; the 93 was like bringing a knife to a gunfight.

Their planning and ours both went out the window when the war started. Both sides had to fight with what they had. In the early years of the war, 42 & 43, the gun fights in the constricted waters of the Solomon Islands were dead even. Those battles were nasty, loud, close and the reason they call a certain body of water Ironbottom sound.