Portuguese Phrase
O que é um detector de fumaça?
Meaning
The sentence asks for a definition or explanation of a smoke detector, a device that senses smoke and alerts people to a possible fire.
When to use
Use this question when you are discussing home safety, fire‑prevention equipment, or when you encounter an unfamiliar device and need clarification.
✦Grammar Breakdown
Oqueéumdetectordefumaça?
O que
Used to form a question meaning 'what'. It is placed at the beginning of the sentence.
é (ser)
Third‑person singular present of the verb 'ser', used for definitions and identity.
um
Indefinite masculine article meaning 'a' or 'an'.
detector de fumaça
Noun phrase: 'detector' (detector) + preposition 'de' (of) + 'fumaça' (smoke).
🗨In Conversation
O que é um detector de fumaça?
What is a smoke detector?
É um aparelho que detecta fumaça e dispara um alarme para avisar sobre risco de incêndio.
It’s a device that detects smoke and triggers an alarm to warn about fire risk.
✕Common Mistakes
O que é um detector de fumo?
While understood, 'fumo' is less common; 'fumaça' is the standard term for smoke in this context.
É um detector de fumaça.
Missing the interrogative 'O que' turns the sentence into a statement.
O que é detector de fumaça?
Dropping the article 'um' makes the phrase sound incomplete in Portuguese.
↔Alternatives
O que significa detector de fumaça?
What does smoke detector mean?
Para que serve um detector de fumaça?
What is a smoke detector used for?
Como funciona um detector de fumaça?
How does a smoke detector work?
Cultural Tip
In Brazil, smoke detectors (often called 'detector de fumaça' or 'alarme de fumaça') are required by law in many residential and commercial buildings. When speaking to a technician or in a formal setting, keep the tone polite and use the full phrase rather than the colloquial 'detector de fumo'.