In rhetoric, a parenthesis

( plural: parentheses;

from the Greek word


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

( Parenthesis )