Wiktionary
n. A non-lethal projectile made of aluminium carcase and plastic head, designed to be fired from a specialized gun, for riot control.
Wikipedia
A plastic bullet or plastic baton round (PBR) is a less-lethal projectile fired from a specialised gun. Although designed as a non-lethal weapon, they have caused a number of deaths. They are generally used for riot control. Plastic bullets were invented in 1973 by the British security forces for use against rioters in Northern Ireland. They were developed to replace their rubber bullets in an attempt to reduce fatalities. If misused they can still cause fatal injury.
An unrelated small-calibre handgun bullet made of plastic is sometimes used for short range target practice (see recreational use).
Usage examples of "plastic bullet".
The plastic bullet caught a man in the middle of his chest, slamming him back into the three behind him.
Frigate took a plastic bullet out of the bag that hung from his belt.
American and European nurses and doctors doing volunteer service in West Bank hospitals reported that Israeli soldiers, deprived of the power of lead, were now shooting the young Arabs in the head at such close range that even a plastic bullet could cause death or brain damage.
The nonmagnetic plastic bullet crashed through his super-powerful defence screen and struck home where Thomas Cardif intended it to.