Synonyms of fatal

fatal

adjective

ˈfā-tᵊl 

1

as in disastrous

bringing about ruin or misfortune

I made the fatal mistake of sharing my secret with the office's biggest blabbermouth

Synonyms & Similar Words

• disastrous
• catastrophic
• unfortunate
• destructive
• fateful
• ruinous
• calamitous
• damning
• adverse
• damaging
• apocalyptic
• harmful
• cataclysmal
• detrimental
• injurious
• pernicious
• deleterious
• luckless
• hapless
• baneful
• evil
• prejudicial
• ill-fated
• ill-starred
• hurtful
• noxious
• ill
• baleful

Antonyms & Near Antonyms

• fortuitous
• lucky
• fortunate
• happy
• providential
• fair
• promising
• fluky
• golden
• optimistic
• propitious
• bright
• encouraging
• hopeful
• rosy
• auspicious
• heartening
• upbeat
• rose-colored

2

as in lethal

likely to cause or capable of causing death

that snake's venom is fatal unless the victim is given the antidote almost immediately

Synonyms & Similar Words

• lethal
• deadly
• poisonous
• infectious
• infective
• killer
• harmful
• terminal
• dangerous
• toxic
• deathly
• mortal
• murderous
• baleful
• injurious
• fell
• destructive
• hazardous
• pernicious
• vital
• deleterious
• pestilent
• serious
• baneful
• virulent
• risky
• perilous
• sublethal
• noxious
• pestilential
• threatening
• ugly
• bloody
• truculent
• grievous
• menacing
• sanguinary
• unhealthy
• grave
• parlous
• unsound
• jeopardizing
• sanguine
• internecine

Antonyms & Near Antonyms

• nonfatal
• healthy
• beneficial
• healthful
• nonlethal
• wholesome
• salutary
• corrective
• salubrious
• remedial
• restorative
• curative
• useful
• advantageous
• tonic
• safe
• nontoxic
• alleviative
• nonpoisonous

Synonym Chooser

How does the adjective fatal differ from other similar words?

Some common synonyms of fatal are deadly, lethal, and mortal. While all these words mean "causing or capable of causing death," fatal stresses the inevitability of what has in fact resulted in death or destruction.

fatal consequences

When is it sensible to use deadly instead of fatal?

While the synonyms deadly and fatal are close in meaning, deadly applies to an established or very likely cause of death.

a deadly disease

When would lethal be a good substitute for fatal?

The meanings of lethal and fatal largely overlap; however, lethal applies to something that is bound to cause death or exists for the destruction of life.

lethal gas

When might mortal be a better fit than fatal?

The synonyms mortal and fatal are sometimes interchangeable, but mortal implies that death has occurred or is inevitable.

a mortal wound

Example Sentences

Recent Examples of fatal

Fatal 737 Max crashes in 2018 and 2019 linked to MCAS software, a 2024 door plug blowout caused by missing factory bolts, and a fatal 2025 Air India 787 crash have intensified global regulatory focus. — Mrigakshi Dixit, Interesting Engineering, 2 Nov. 2026

The Porter County Sheriff’s Department is investigating two fatal wrecks over the weekend. — Post-Tribune, Chicago Tribune, 2 Nov. 2026

Career prosecutors later realized the potentially fatal mistake and tried to raise it before the case was charged. — Sarah N. Lynch, CBS News, 2 Nov. 2026

The two fatal shootings were Kansas City’s 113th and 114th homicides of 2026, according to The Star’s database, which also includes fatal police shootings. — Nathan Pilling, Kansas City Star, 2 Nov. 2026