When a friend of the opposite sex (for heterosexuals) wears something slightly revealing or otherwise shows a bit of skin, and it would be rude or confidence destroying not to take a quick glance.
Claire just got changed on the bus, would have been rude not to give her a courtesyperv
When you are watching a movie with a bro and a sad part comes up. Your bro begins to cry so you throw your drink in their face so no one can see that he is crying.
Dude, thanks for that courtesysplash when Obi-Wan died. I would have been hella embarrassed.
slut. someone who sluts around and sleeps with everybody's boyfriends. she is a home wrecker who needs to be shot in the head. dont go near her or you willcatch an std.