Boldface (noun)

1. A typeface that is thicker and darker than the surrounding text.
2. The action of making text boldface.

Origin:

The term boldface is derived from the practice of printing the text in a heavier or darker font to make it stand out from the surrounding text. the term has been used since the early days of printing and typesetting.

Examples:

1. The title of the article was in boldface to make it stand out.
2. The instructions asked to type the word in boldface.
3. The resume was typed in a boldface font to make it easy to read.
4. The teacher asked the students to underline the boldface words in the reading.
5. The menu was written in a boldface font to make it easy to read.