Didn't do anything significant. I don't understand why he's so conceited—he didn't invent gunpowder or anything!See also: invent
didn't invent gunpowder
Rur. did not do anything terribly important. He may be the class president, but he didn't invent gunpowder.What's all this fuss about a movie star? She didn't invent gunpowder!See also: invent