Which one should you use?
thối is about organic decay. The word hỏng is more general and means broken or spoiled, so it is used for things like electronics that stop working as well as food that has gone off in a general sense. For food that is actually decaying and smells bad, thối is the precise word.
How does it change in a sentence?
When you describe something that has gone through the process of rotting, thối is often preceded by the passive marker bị, giving bị thối, which means to be rotten or to have gone rotten. Vietnamese adjectives work like verbs, so thối can follow the noun directly with no word for is, as in Trứng thối.
What mistakes should you avoid?
Do not use hỏng when you mean food is rotting and smells bad. Use thối for that, and keep hỏng for things that are broken or spoiled in a general way.
Did you know?
- There is a separate Sino-Vietnamese word thối derived from the Chinese character 退, which relates to retreating or declining rather than decaying.
- The word thối can be used as a sharp insult for someone with a corrupt or immoral character, mirroring the English concept of a 'rotten' person.
- The phrase bị thối uses the marker bị, which is specifically reserved for experiences that are negative or unfortunate.
Examples in context
- Một nửa số quả táo đã bị thối.Half of these apples are rotten.Here đã bị thối combines a past marker with bị thối to say the apples have already gone rotten.Tatoeba #13726676 by leucammieuvu, translation #55274 by CK
- Trứng thối.The eggs are rotting / have rotten.Trứng thối is a short statement where thối follows the noun directly to say the eggs are rotten.
- Bữa trưa người ta đã phát hiện một quả táo thối trong hộp đồ ăn.During lunchtime, someone discovered a rotten apple in the lunchbox.
Example conversation
Tuấn and Hương are inspecting food in the kitchen.
- TuấnHương ơi, rau này có bị thối không?Huong, is this vegetable rotten?
- HươngCó, nó bị thối rồi, đừng ăn nhé.Yes, it is rotten, don't eat it.
- TuấnThật là tệ quá.That is too bad.
- HươngĐể em đi vứt nó đi.Let me go throw it away.
Sources
- Pronunciation: Wiktionary entry thối, CC BY-SA 4.0, dump of 2026-09-26.
- Word origins: Wiktionary entries thối, CC BY-SA 4.0.
- Example sentences: Tatoeba CC BY 2.0 FR, Wiktionary CC BY-SA 4.0.