The apple functioned as a generic label under which new foods entered languages

Evidence

We find plenty of references to fruits and vegetables, including figs, dates, grapes, peaches; eggplant is a great staple. The apple seems to be so basic that it even serves as a sort of generic term for fruits and vegetables, so that something unfamiliar is called a kind of apple. An Italian pilgrim, describing his first encounter with a banana in Egypt in 1384, calls it a “paradise apple.” When the potato, an American innovation, first appeared, the French called it pomme de terre. When modern Israel needed names for oranges and potatoes, lacking in biblical and rabbinic Hebrew, they both became apples of a kind: “golden apples” and “earth apples.” And when the tomato was introduced to Italy, it was the “golden apple,” the pomodoro, which eventually passed into Arabic in the forms banadura and bandura. — Bernard Lewis, From Babel to Dragomans, 246

Categorization

• CANDY: The ‘apples of a kind’ naming pattern — pomodoro, pomme de terre, paradise apple, golden apples for oranges — is a deliciously tweetable linguistic tidbit.
• XREF: Shows how unfamiliar foods get domesticated by assimilating them to known categories — a micro-version of knowledge-production legibility themes.