Boundlessly energetic. Moxie was a carbonated soft drink that began life at the end of the 19th century as a medicinal tonic (its inventor named it after a friend who supposedly discovered its key but unspecified ingredient). Thanks to an aggressive advertising campaign and key endorsements, Moxie became a nationwide success until World War II. It's now popular primarily in the New England area and Pennsylvania. Gentian root gave Moxie its distinctive sharp flavor, which led to claims that it had energizing qualities. Hence the notion that someone who was feeling full of life was “feeling his Moxie.” Another peppy phrase comes from a breakfast cereal: “feeling your Wheaties.”