1. the act of biting the corner of your bottom lip, tucking it in slightly, as your eyes move over the tits of hot chick
2. the act of moving your eyes down then back up a womanly figure, then biting the corner of your bottom lip, tucking it in slightly, as your gaze meets the tits
Girl #1: See that guy across the bar!? He's totally into you!
Girl #2: No way!
Girl #1: That was the second Titty Tuck he's given you tonight.