Part of Speech: Article, Conjunction
Pronunciation: dhê (before consonants: the dog), dhee (before vowels: the apple).
Meaning: 1. (Article) The definite article marks nouns referring to things the speaker expects the listener to be familiar with. “A dog” refers to any mutt, while “the dog” refers to one the listener sees or knows about from a previous conversation. 2. (Conjunction) Comparative conjunction: “The more the merrier.”
Notes: An interesting fact about the is that it is used differently in different dialects. Everyone says “in school” and “at work” without the, but the British also drop it from “in hospital”, “in future”, and elsewhere. If you watched the popular British television series All Creatures Great and Small, you probably noticed that in Yorkshire people also say things like, “I’ll go to kitchen and put kettle on.” Actually, there is a barely audible glottal stop where we expect the, the remnants of the final [t] in that.
In play: When an object is unique, the is usually required: “the sun”, “the moon”, and others. In German the equivalent of the is used before proper nouns under certain circumstances, e.g. der Hans “(the) Hans”, die Grete “(the) Grete”. Greek does the same. In Swedish, the definite is expressed by a suffix on nouns: en dag “a day”, dagen “the day”. Bulgarian does the same: student “student”, studentêt “the student”. That [t] at the end of the Bulgarian word is not coincidental; it comes from the same root as English that.
Word History: Relatively few languages in the world have definite (the) and indefinite (a) articles. English a is a reduction of Old English an “one” (compare German ein “one, a”) and the is a reduction of that (compare German das “that, the”). In French (le, la), Italian (il, lo, la), and Spanish (el, lo, la) all come from Latin ille “that”. The equivalent of a in all these languages also comes from the word for “one”. (Great gratitude today is due Paige Turner for not overlooking the fascinating world of the minuscule.)