lethal
LEE-thuhl
/ˈliː.θəl/
Sufficient to cause death; deadly or fatal.
Carries a cold, clinical tone indicating extreme effectiveness in inflicting death.
The story behind the word. Rooted in Latin 'letalis' (causing death), from 'letum' (death). Post-medieval scholars blended it with Greek 'Lethe', the underworld river of oblivion whose waters caused souls to forget their past lives.
Word relationships
- fatal: Fatal emphasizes that death actually resulted; lethal describes the capacity to cause death.
- deadly: Deadly is broader and more conversational; lethal is clinical and standard in scientific/military contexts.
- non-lethal: Designed specifically to subdue or incapacitate without causing death.
- harmless: Incapable of causing injury or harm.
Commonly confused with
- harmful: Harmful means causing damage or injury, whereas lethal specifically means causing death.
Word family
- lethality (noun): The capacity to cause death.
- lethally (adverb): In a deadly manner.
Collocations
- lethal dose
- lethal force
- lethal agent
- potentially lethal
Example sentences
- "VX nerve gas is among the most lethal chemical compounds ever synthesized, causing death within minutes of skin exposure." Military Assessment
- "The military tribunal differentiated between lethal weaponry and non-lethal crowd-control agents." Legal & Strategic Definition
Memory hook
LETHAL leads to LETHE—the river of death and forgetting. Capable of causing death.
When not to use
Avoid hyperbole in technical writing—do not call mild irritants or non-fatal agents 'lethal'.
Fun facts
- In toxicology, LD50 stands for 'Lethal Dose, 50%', measuring the exact concentration of a substance required to kill half of a tested population.
Related words
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