The definition of a boom is a loud deep sound that is often very surprising.(noun)
An example of boom is the sound a car makes when it backfires or the sound a balloon makes when it pops.
See boom in Webster's New World College Dictionary
Origin: ME bummen, to hum; like Du bommen, Ger bummen, orig. echoic
Origin: from use of ship's boom for this purposea long beam extending as from an upright to lift or carry something and guide it as needed: the boom of a derrick, a microphone boom
Origin: Du, a tree, beam, pole; same word ult. as beam
Origin: < ? boomvi.; later assoc. with boom
See boom in American Heritage Dictionary 4
verb boomed, boom·ing, booms verb, intransitive
Origin: Middle English bomben, imitative of a loud noise.
Origin: Dutch, tree, pole
Origin: , from Middle Dutch; see bheuə- in Indo-European roots.
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