The definition of a patina is a crust or film, that happens from use or exposure to oxygen.(noun)
See patina in Webster's New World College Dictionary
Origin: Fr < It, orig., tarnish (on a metal plate), prob. < L, pan: see patella
See patina in American Heritage Dictionary 4
noun pl. pat·i·nae (pătˈn-ē)
Origin: Medieval Latin
Origin: , from Latin, plate; see paten.
Origin: , from Latin, plate (from the incrustation on ancient metal plates and dishes); see paten.
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