Toxic herbicides are chemical compounds used to kill weeds and other unwanted plants. Two of the most well-known toxic herbicides are Paraquat, an 8-letter word, and Agent Orange, an 11-letter word. Paraquat is a non-selective herbicide that kills all plants it comes into contact with, while Agent Orange is a defoliant used by the United States military during the Vietnam War. Both of these herbicides have been linked to serious health problems in humans and animals.