A markup may refer to any of the following:
How to enable Markup in Microsoft Word
You can enable and disable what markup is shown in Microsoft Word by clicking the Review tab and selecting the "Show Markup" option and check or uncheck the markup you want to view.
2. With computers and programming languages a markup is a code, name, or tag used to define the layout or style of how a text is displayed. For example, with HTML (hypertext markup language) that is used to create web pages on the Internet the <b></b> tag (markup) is used to bold text on a page. See our markup language page for a full definition of markup languages and examples of other markup languages.
3. When dealing with a price or money, a mark up or markup is an increase in price from the original retail cost. The higher the mark up the more money (margin) the retailer will make when selling each unit with a mark up.