|a chattering or flighty, light-headed person.|
|a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison.|
rev (sth) up definition
Increase the speed or rate of, enliven, stimulate, as in Bill revved up the motor, or They looked for ways to rev up the ad campaign. The verb rev is an abbreviation for revolution, alluding to the rate of rotation of an engine. The idiom dates from about 1920 and has been used figuratively since the mid-1900s.