drugstore cowboy
1. A young man who loiters in public places, such as on street corners or outside of drugstores, especially in the attempt to impress or woo young women. Primarily heard in US, South Africa. I hate going through this area, there's always a few drugstore cowboys cat-calling me when I pass by.
2. A person who dresses and acts like a cowboy but who has never worked as one and has none of a cowboy's skills or experience. Originally a reference to extras in Hollywood western films (who would remain in costume off set), it later extended to anyone who wears cowboy clothing purely for the purposes of style or affectation. Primarily heard in US, South Africa. The senator accused his challenger of being a drugstore cowboy—a city slicker who had no idea what it meant to live or work in the rural countryside.
3. One who sells, steals, and/or gets high on prescription or over-the-counter medications. Primarily heard in US, South Africa. Police apprehended a drugstore cowboy who held up a local pharmacy and made off with loads of prescription medication.
cowboy up
To act tough and determined, like a stereotypical cowboy. Come on, dude, cowboy up! We can totally make that jump on our bikes!