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que, qué (Interrogative Pronoun, Conjunction) "what;" "that;" "than"
10th cent. Old Spanish que "that;" 12th cent. qué "what." Semantically the result of a collapse of Latin quid "what" and qui "who" into a single word; phonologically the word comes from quem, the accusative of qui (see quien).
Also used as an interjection, ¡Qué casualidad! "What a coincidence!"
Indo-European
Celtic
Old Irish cía "who," Old Welsh pui 'id.,' Old Breton pou 'id.,' Cornish pyw 'id.'
Germanic
Gothic ƕas "who," Old Norse hverr 'id.,' Old High German hwer 'id.,' Old Saxon hwē 'id.,' Old English hwā 'id.' (English who)
Hellenic
Ancient Greek τίς (tís) "who," Thessalian κις (kis) 'id.,' Mycenaean jo-qi- 'id.'
Phrygian
Phrygian κιν (kin) "whom"
Indo-Iranian
Sanskrit kím "what," "what for," Young Avestan cim "because"
Tocharian
A kus "who," B kuse 'id.'