A correspondent sent me a link to Mark Forsyth’s The Inky Fool post on the etymology of taser, remarking that it was news to him. It’s news to me, too, and I quote Mark’s post, which tells the story well:
The taser was invented by a NASA scientist called Jack Cover who worked on it between 1969 and 1974. He had been inspired by a series of children’s books about a hero called Tom Swift. Tom Swift is an adventuring sort of chap who goes around having adventures, sometimes in darkest, deepest Africa and sometimes on the Moon. There have been over a hundred Tom Swift books published since 1910 and they still seem to be going strong, there was even a Tom Swift board game once. However, the one that interests us is the tenth in the series which was published in 1911: Tom Swift and his Electric Rifle. In this one Tom Swift goes elephant hunting when he discovers that some of his friends have been taken hostage by a tribe of red pygmies. Luckily for the hero (but unluckily for the red pygmies) Tom has with him his brand new invention: a rifle that uses electricity rather than bullets. It can therefore be set to different ranges and different levels of lethality, so he can stun elephants, kill pygmies etc.
It was this invention that Jack Cover was attempting to imitate, and he even decided to call it Tom Swift’s Electric Rifle, or TSER. However, as that didn’t make a catchy acronym he decided to add a gratuitous initial and make it Thomas A. Swift’s Electric Rifle, or TASER.
Of course, it occurred to me that it might be too good a story, and my suspicions were aroused when neither M-W nor AHD had it, but then I turned to the OED and found “Etymology: Acronym < the initial letters of Tom Swift’s electric rifle (a fictitious weapon), after laser n.” If it’s good enough for the OED, it’s good enough for me. (Thanks, Bruce!)