See sunbeam in American Heritage Dictionary 4
Origin: Middle English sunnebem
Origin: , from Old English sunnebēam (translation of Late Latin columna lūcis, pillar of light)
Origin: : sunne, sun; see sun
Origin: + bēam, tree, building post; see beam. Word History: Though the period of European history from the 5th to the 11th century is often called the Dark Ages, writers and scholars of the time in fact did much to preserve and extend the light of civilization. A minor but felicitous contribution to the English language from this period is the word sunbeam, which is believed to have entered English in the 9th century through the work of Alfred the Great. A scholar as well as a king, Alfred undertook and oversaw the translation of a number of Latin works into the English of his time, now known as Old English. Among these was The Ecclesiastical History of the English People, a work composed by the Venerable Bede. The Latin phrase columna lūcis, which we would today translate as “a column of light,” occurs several times in this work. Since the Old English translator did not have the word column in his vocabulary, he used bēam, which meant “a tree” or “a building post made from a tree” (our modern word beam). Columna lūcis thus became sunnebeām, or “sun post,” which survives as our sunbeam. Though perhaps less stately than “column of light,” sunbeam has brightened our language. From it the word beam alone came to mean “a ray or rays of light”; it subsequently became a verb meaning “to radiate.” It now allows us not only to beam with pride or happiness but also to beam our broadcasts around the earth and even to the stars.
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