who (pron.) Look up who at Dictionary.com
Old English hwa "who," sometimes "what; anyone, someone; each; whosoever," from Proto-Germanic *hwas (source also of Old Saxon hwe, Danish hvo, Swedish vem, Old Frisian hwa, Dutch wie, Old High German hwer, German wer, Gothic hvo (fem.) "who"), from PIE root *kwo-, stem of relative and interrogative pronouns.