lethal

Something that is lethal can cause death. It is a strong word, usually used for things that are extremely dangerous, such as poison, weapons, or a disease that can kill. You would not use it for a small cut, but you might use it for a dose of cyanide or a snake bite from a very dangerous species. The word often suggests that death is a real and serious risk if the thing is touched, used, taken, or met. Common phrases include "lethal injection" and "lethal weapon."

The word "lethal" describes anything that has the power to cause death. It goes beyond simply being "dangerous" because it suggests a serious chance that someone or something could die. Think of a predator like a lion: its claws and teeth are lethal in a hunt. In the same way, a hurricane's storm surge can be lethal if people are not evacuated in time.

Etymologically, "lethal" traces back to the Middle French word letal and the Latin letalis, which stems from letum, meaning "death." This direct linguistic connection to mortality gives the word its serious and often ominous tone. While "fatal" is often used to describe an event that has already resulted in death (like a fatal car accident), "lethal" more frequently describes the capacity of an object or substance to kill (like a lethal dose of medication).

Beyond physical threats, "lethal" is also used figuratively to describe something powerfully damaging or effective. For instance, a critic might deliver a "lethal" review that destroys a playwright's reputation, or a tennis player might have a "lethal" serve that opponents cannot return. Even in these figurative uses, the word keeps its core idea of bringing a decisive and damaging result. Whether it describes a poison, a weapon, or a sharp comment, "lethal" points to a force with severe, often final consequences.