[adjective] - being a word such as 'this', 'that', 'these' and 'those' which shows which person or thing is being referred toIn the sentence 'This is my brother', 'this' is a demonstrative pronoun.See also demonstrative at demonstrate (SHOW), demonstrate (EXPRESS).
DEMONSTRATIVE
Meaning of DEMONSTRATIVE in English
Cambridge English vocab. Кембриджский английский словарь. 2012