to make someone feel more confident, resolved, or bold, to offer them encouragement that gives them the courage to overcome doubts or timidity and do something;
e.g. She hopes her words will embolden them to choose the right course of action, even if it is difficult.
(verb)
to make a piece of text appear in bold type/font, i.e. to to cause to appear in boldface;
e.g. Make sure you embolden the key words in the message.