ACORN  , the

fruit of the oak-tree; a word also used, by analogy with the shape, in nautical language, for a piece of wood keeping the vane on the mast-head . The etymology of the word (earlier akerne, and acharn) is well discussed in the New English Dictionary . It is derived from a word (Goth. akran) which meant " fruit," originally " of the unenclosed land," and so of the most important forest produce, the oak . Chaucer speaks of " achornes of okes." By degrees, popular etymology connected the word both with " corn " and " oak-horn," and the spelling changed accordingly .