Definition of "italicize" [i•tal•i•cize]

• To print in italic type. (verb-transitive)
• To underscore (written matter) with a single line to indicate italics. (verb-transitive)
• To emphasize: "italicizing the upper extremity of the pitch spectrum with flute or piccolo” ( Arthur Berger). (verb-transitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Why does Díaz not italicize the Spanish words (the way foreign words are usually italicized in"
• "The standard instruction to typesetters to italicize a word in a handwritten manuscript or a proof was to draw a line underneath it."
• "I will suggest that the reason people still underline is that many of the results of googling “manuscript format” state most firmly that to italicize is to err."