Synonyms of the word

lethal

• adj. Deadly; mortal; fatal.
• n. (chemistry) One of the higher alcohols of the paraffine series obtained from spermaceti as a white crystalline…

deadly

• adj. (obsolete) Subject to death; mortal.
• adj. Causing death; lethal.
• adj. Aiming or willing to destroy; implacable; desperately hostile.
• adj. (by extension) Very accurate (of aiming with a bow, firearm, etc.).
• adj. (informal) Very boring.
• adj. (informal) Excellent, awesome, cool.
• adv. (obsolete) Fatally, mortally.
• adv. In a way which suggests death.
• adv. Extremely.

fatal

• adj. Proceeding from, or appointed by, fate or destiny.
• adj. Foreboding death or great disaster.
• adj. Causing death or destruction.
• adj. (computing) Causing a sudden end to the running of a program.
• n. A fatality; an event that leads to death.
• n. (computing) A fatal error; a failure that causes a program to terminate.