having an even and regular surface; free from perceptible projections, lumps, or indentations
smooth flat rocks
his face was curiously smooth and youthful
(of movement) without jerks
the trucks gave a smooth ride
graphics are excellent, with fast, smooth scrolling
(of an action, event, or process) without problems or difficulties
the group's expansion into the US market was not quite so smooth
(of a person or their manner) suavely charming in a way regarded as possibly insincere
his voice was infuriatingly smooth