Parenthesis (rhetoric)

In rhetoric, a parenthesis (plural: parentheses; from the Greek word παρένθεσις parénthesis, which comes in turn from words meaning "alongside of" and "to place") or parenthetical phrase is an explanatory or qualifying word, clause, or sentence inserted into a passage. The parenthesis could be left out and still form grammatically correct text. Parentheses are usually marked off by round or square brackets, dashes, or commas.

The following are examples of types of parenthetical phrases:

While a parenthesis need not be written enclosed by the curved brackets called parentheses, their use, principally around rhetorical parentheses, has made the punctuation marks the only common use for the term in most contexts.

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