| Main Entry: | |
| Part of Speech: | adjective |
| Definition: | causing end of life |
| Synonyms: | baleful, baneful, bloodthirsty, bloody, cannibalistic, carcinogenic, cruel, dangerous, death-dealing, deathly, deleterious, destroying, destructive, fatal, grim, harmful, homicidal, injurious, internecine, killing, lethal, malignant, mortal, mortiferous, murderous, noxious, pernicious, pestiferous, pestilent, pestilential, poisonous, ruthless, savage, slaying, suicidal, toxic, unrelenting, venomous, violent, virulent |
| Notes: | deadly means causing or capable of causing death while deathly means having the physical appearance of death |
| Antonyms: | animating, energizing, harmless, healthful, healthy, invigorating, wholesome |
| Main Entry: | fatal |
| Part of Speech: | adjective |
| Definition: | deadly, lethal |
| Synonyms: | baleful, baneful, calamitous, cataclysmic, catastrophic, deathly, destructive, disastrous, fateful, final, ill-fated, ill-starred, incurable, inevitable, killing, malefic, malignant, mortal, mortiferous, noxious, pernicious, pestilent, pestilential, poisonous, ruinous, terminal, virulent |
| Notes: | use fatal for something which has caused someone's death; use lethal for something which is capable of killing someone |
| Antonyms: | healthful, life-giving, nourishing, vital, wholesome |
| Main Entry: | lethal |
| Part of Speech: | adjective |
| Definition: | deadly |
| Synonyms: | baleful, dangerous, deathly, destructive, devastating, fatal, harmful, hurtful, malignant, mortal, mortiferous, mortuary, murderous, necrotic, noxious, pernicious, pestilent, pestilential, poisonous, virulent |
| Notes: | use fatal for something which has caused someone's death; use lethal for something which is capable of killing someone |
| Antonyms: | beneficial, harmless, helpful, life-giving |
| Main Entry: | mortal |
| Part of Speech: | adjective |
| Definition: | deadly |
| Synonyms: | bitter, death-dealing, deathly, destructive, dire, ending, extreme, fatal, grave, great, grievous, grim, intense, killing, last, lethal, malignant, merciless, monstrous, mortiferous, murderous, noxious, pestilent, pestilential, poisonous, relentless, remorseless, ruthless, severe, terminal, terrible, unrelenting |
| Antonyms: | invigorating, lifegiving, permanent, refreshing |