a line drawn underneath (especially under written matter)
draw a line or lines underneath to call attention to
a single character wildcard, matching zero or one characters
To underline. To create a line beneath type, whether a letter, word, or sentence. Underscoring generally serves to add emphasis. See also EMPHASIS UNDERLINE
line appearing on the baseline beneath a word or phrase notating italic type (e.g., " Dynamic Graphics magazine"); now more commonly used in e-mail addresses