Qenya
aiane
pronoun. anybody (thing, one) else; someone else, another
Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!
The correlative personal pronouns ᴹQ. aiane or aine “anybody (thing, one) else; someone else, another” appeared Demonstrative, Relative, and Correlative Stems (DRC) from 1948 (PE23/103 and note #42), both pronominal forms of ᴹQ. aia- “other”. These replaced various rejected forms: {arane, are} >> {warane, ware} >> {astane, asse, anasse} >> aiane, aine.
Conceptual Development: The Early Qenya Grammar of the 1920s had ᴱQ. nyando, [nyand]e and nyan, apparently masculine, feminine and neuter pronouns for “another, other (of many)”, as opposed to ᴱQ. etyo, [ety]e “other (of two)” (PE14/55). The actual glosses Tolkien gave were “alter” and “alius”, which are Latin for “the other (of two)” and “another, other (of many)” according to the Carl Hostetter and Bill Welden (PE14/56 note #97).
Neo-Quenya: For purposes of Neo-Quenya I would use ᴺQ. hyaquen for “someone else, another”, a combination of Q. hya “other” and quén “person”.