1. To make something neat, shiny, even, or level: Jim was making every effort to smooth the plaster on the walls and ceiling of the living room before he painted it and put on the wallpaper.
2. To refine, polish, perfect, or facilitate: Betty smoothed out her musical presentation so she would be ready for the concert.
3. To calm, mollify, assuage, or to tone down: The head of the city council smoothed the discontent of the citizens with more acceptable solutions.