Fast-talking is a term used to describe someone who speaks quickly and persuasively, often in an attempt to sell something. Synonyms for fast-talking include glib, slick, smooth-tongued, articulate, loquacious, voluble, and silver-tongued. These adjectives all suggest a person who is skilled at using language to their advantage, and who is able to persuade others with their words. While these traits can be useful in certain situations, they can also be seen as manipulative or disingenuous. It's important to be aware of how our words can be perceived, and to strive for honest and authentic communication in all our interactions with others.