A Taser is a weapon that looks a bit like a small gun. It fires two little darts that stay joined to it by thin wires, and it sends a strong electric current down those wires into the person's body. The muscles tighten so hard the person cannot control them, and they usually fall over. It hurts a great deal but is not meant to kill; police carry one so they have something between shouting and shooting. Two things about the word are worth knowing. First, it started as a brand name — a company's product — which is why you often see it with a capital T, and careful newspapers keep the capital. But so many people now use it for any weapon of this kind that the small-letter 'taser' is everywhere too, the same way 'Hoover' or 'Xerox' slipped into ordinary English. Second, it is also a verb: 'the police tasered him.' A shorter verb 'tase' grew out of it as well, so both 'tasered' and 'tased' are in use. You will meet the word mostly in news, in crime dramas, and in arguments about the police, because it is a word people fight over — is it a kind way to stop someone, or a way of hurting people who are already helpless? Because the weapon is rare in Taiwan, the word here belongs mostly to foreign news rather than daily life.