pronoun
Etymology: Middle English such an on
1. : one of this or that kind : one of a specified or understood kind
he knows who is a likely witch and takes such a one in hand by commonsense methods — W.W.Howells
2.
a. : one of a kind to be indicated or specified
such a one as may be found in any small town
b. : one of the same kind
just such a one as his father
3. archaic : someone not named
telling you then … that such a one and such a one were past cure — Shakespeare