Thisthese
Thisthese is a neologism used in some linguistic discussions to denote the small set of proximal English demonstratives consisting of this and these. The term is not part of standard grammar, but it appears in analytical glossaries and typological surveys as a convenient label for the near-demonstrative determiners that mark proximity and, in the plural case, number. By grouping this and these under a single label, researchers can compare proximal demonstratives across languages or chart their behavior in corpora without repeatedly listing the two forms.
In standard English, this functions as a singular proximal determiner, as in this book, while these functions
Critics argue that the label offers little empirical advantage and may obscure the distinct grammatical properties
See also: demonstratives, deictics, proximate demonstratives, English determiners.