General English

  • adjective used to show something or someone that is further away or in the past
  • adverb to such a degree
  • conjunction used after verbs like ‘say’ or ‘think’ and adjectives like ‘glad’ or ‘disappointed’, and after ‘so’ or ‘such’
  • relative pronoun used to give more information about someone or something just mentioned

Origin & History of “that”

That is a very ancient word, going right back to prehistoric Indo-European *tad (source also of Greek ‘the’ and Russian tot’, ta, to ‘that’). Its original function in English was as the neuter form of a demonstrative pronoun. this came to be used as the definite article (modern English the), but as the grammatical gender system began to break down in the early middle English period, that broke away from the definite article and began to be used as a demonstrative adjective. Its use as a relative pronoun goes back to the Old English period.