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Parallelism (grammar) In grammar, parallelism, also known as parallel structure or parallel construction, is a balance within one or more sentences of similar phrases or clauses that have the same grammatical structure. The application of parallelism improves writing style and readability, and is thought to make sentences easier to process.
Dictionary of Construction. A panel or group of individual panel units capable of being assembled as a single panel and designed to include fuses, switches, and circuit breakers. The units are housed in a cabinet or cutout box positioned in or against a wall or partition and accessible only from the front.