parenthesis

Either or both of the upright curved lines, ( ), used to mark off explanatory or qualifying remarks in writing or printing or enclose a sum, product, or other expression considered or treated as a collective entity in a mathematical operation.

A qualifying or amplifying word, phrase, or sentence inserted within written matter in such a way as to be independent of the surrounding grammatical structure.

A comment departing from the theme of discourse; a digression.

An interruption of continuity; an interval.

An explanatory or qualifying clause, sentence, or paragraph inserted in another sentence or in the course of a longer passage, without being grammatically connected with it.