Throughout is defined as in every part, during every part or all the way through.(preposition)
An example of throughout used as a preposition is in the sentence, "The park is open throughout the year," which means that the park is open year round.
Throughout means in or during the entire time or part.(adverb)
An example of throughout used as an adverb is in the sentence, "He remained relaxed throughout the surgery," which means that he was relaxed for the whole surgery, from start to finish.
See throughout in Webster's New World College Dictionary
See throughout in American Heritage Dictionary 4
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