1 SURFACE: A smooth surface has no rough parts, lumps or holes, especially in a way that is pleasant and attractive to touch
Her skin felt smooth and cool.
a smooth pebble
The stone steps had been worn smooth.

2 happening whithout problems happening or operating successfully , whithout any problems
smooth running/operation
Sarah is responsible for the smooth running of the sales department.
The new government has promised the smooth transition of power.
➔ go smoothly at smoothly (2)

3 MOVEMENT [only before noun] with no sudden movements or changes of direction, especially in a way that is graceful or comfortable.
Swing the tennis racquet in one smoth motion
The jet made a smooth landing
smooth flight/ride (=a comfortable trip in an airplane or car)
It wasn't a smooth ride

4 PERSON someone who is smooth is polite, confident, and relaxed, but is often not sincere
A smooth salesman
He was a smooth talker
George is a smooth operator (=someone who does things in a smooth way).

5 LIQUID MIXTURE a liquid mixture that is smooth has no big pieces in it [≠ lumpy]:
Beat the eggs and flour until they are smooth.

6 SOUND a voice or music that is smooth is soft and pleasant to listen to:
smooth jazz
He has one of those silky smooth (=very smooth) voices.[/b]

7 TASTE a drink such as wine, coffee, whisky, or beer that is smooth is not bitter but tastes pleasant:
a smooth full-bodied wine
smoothness [noun] [uncountable]
the smoothness of his skin
➔ smooth-talking