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manzana (1) f. (Noun) "apple"
12th cent. Old Spanish mazana. From Vulgar Latin mattiana 'id.' From Latin mala Mattiana, a golden apple varietal but lit. "Matian apples." Named after the horticulturist Gaius Matius, friend of Cæsar Augustus, whom Pliny the Elder said introduced the art of clipping trees. Mala "apples" (singular malum) was borrowed from Ancient Greek μῆλον ‎(mêlon) "fruit," "tree." Of unknown origin.
Also the origin of the surnames Manzanas and Mansana.