Buck up

To buck up can mean various things depending on the context. It can mean to cheer up or it can mean to hurry up, get a move on, or improve one’s status, as in ‘buck up one’s ideas’. All these meanings date from the mid-19th century and derive from the early 18th century when a young buck was the term for a lusty young man with obvious reference to the male deer. To buck up originally meant to smarten up in the sense of dressing smartly and looking the part of a young-man-about-town. This would naturally lift one’s spirits. By the mid-19th century, the dressing up connotation had fallen away and it had acquired its current meaning.