Something that's lilting is musical or rhythmic. A lilting voice has a happy, sweet-sounding cadence.
Use the adjective lilting when you talk about something that swings musically along. Your favorite teacher's lilting voice might keep all of her students focused on her class, for example. Or you might choose to sing a lilting song as a way of cheering up a sad toddler. While the sixteenth century meaning was something closer to "lifting up," by the late 1700's to lilt was "to sing in a light manner."