used before a noun to show that the speaker is talking about one specific person, place, or thing that both the speaker and listener already know about
Close the door, please.
We went to the park after lunch.
✦ Old English “þe,” a relative pronoun and definite article, from Proto-Germanic roots related to demonstratives.
used with a comparative adjective or adverb to show how one thing changes in direct relation to another
The more you study, the easier the test will feel.
After a good night’s sleep, she felt all the better.
✦ Same origin as the definite article, later extended to this comparative construction in Middle English.