Plural of cornucopia; multiple horns of plenty or sources of abundant supply.
From Latin cornucopia (horn of plenty), itself from cornu (horn) and copia (abundance). The plural -ae preserves the Latin form, common in scientific and formal English.
The cornucopia myth came from the Greek story of Zeus's nurse Amalthea, whose goat's horn broke off and magically filled with whatever the holder desired—one broken horn became the ultimate symbol of infinite abundance.
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