Word of the Day: April 29, 2009 ~ parenthesis

parenthesis (puh-ren-thuh-sis) - noun

Parenthesis are "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."

Originally used in the written form around 1560-1570. From Late Latin, insertion of a letter or syllable in a word.  From the Greek word parentithenai, meaning "to insert" or "put in beside," from para- "beside" + en- "in" + tithenai "put, place."

Extension of the word to the curved brackets that indicate the words inserted is from 1715.