Why is the fruit of an oak tree called an
acorn?
Acorn derives from the Old English
æcern, which meant "fruit" or "berry." Its transition from
æcern to the modern-day
acorn was the result of phono-semantic matching: Speakers misinterpreted
æcern as
oak corn, logically thinking it was called such because it was the seed (or
kernel) of the oak tree (in Old English,
ac = oak).
Literally:
"oak kernel"
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