In English, the definite article is the word the. It is used before a noun to define it as something specific. It could be something:
- previously mentioned
- being identified by the speaker
- Look at the green car.
(This means a specific car. Maybe it is the only green car in the car park.)
- Can we go to the zoo?
(This means a specific zoo. It is known to the speaker and the listener.)
Compare with an indefinite article.