the

Concise Oxford English Dictionary © 2008 Oxford University Press:
the/ðə/

▶determiner

• 1 denoting one or more people or things already mentioned or assumed to be common knowledge; the definite article.

  ■ used to refer to a person, place, or thing that is unique.

  ■ (with a unit of time) the present.

  ■ informal used instead of a possessive.

  ■ used with a surname in its plural form to refer to a family or married couple.

• 2 used to point forward to a following qualifying or defining clause or phrase.

  ■ (chiefly with rulers and family members with the same name) used after a name to qualify it.

• 3 used to make a generalized reference rather than identifying a particular instance.

• 4 enough of.

• 5 (pronounced stressing ‘the’) used to indicate that someone or something is the best known or most important of that name or type.

• 6 used adverbially with comparatives to indicate how one amount or degree of something varies in relation to another.

  ■ (usu. all the ——) used to emphasize the amount or degree to which something is affected.

– origin OE se, sēo, thæt, ult. superseded by forms from Northumbrian and North Mercian thē, of Gmc origin.