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puerro m. (Noun) "leek"
13th cent. From Latin porrum 'id.' From Proto-Italic *porso- 'id.' From Proto-Indo-European *pr̥so- 'id.' Borrowed from a non-Indo-European language. It's difficult to connect the Indo-Iranian meanings of "ear of corn" with the Latin and Greek meanings of "chives." Therefore, despite the phonological congruity, it may be that the Greek and Latin words were borrowed from a non-Indo-European language spoken near or in Europe, and do not stretch back to Proto-Indo-European. See also de Vaan (2015).
Indo-European
Romance
Portuguese porro, Galician porro, Catalan porro, French poireau, Italian porro, Romanian por
Hellenic
Ancient Greek πράσον (práson) "leek"
Indo-Iranian
Sanskrit parṣá- "sheaf," Young Avestan parša- "ear of corn"