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early 15c., from Latin sardina, from Greek sardine, sardinos, often said to be from Sardo "Sardinia" (see Sardinia), the Mediterranean island, near which the fish probably were caught and from which they were exported. But cf. Klein: "It is hardly probable that the Greeks would have obtained fish from so far as Sardinia at a time relatively so early as that of Aristotle, from whom Athenaios quotes a passage in which the fish sardinos is mentioned." Colloquial phrase packed like sardines (in a tin) is recorded from 1911.