smooth as glass

(as) smooth as glass

1. Of water, exceptionally still and tranquil. Without even the slightest of breezes, the entire lake was smooth as glass.
2. Of some solid surface, exceptionally smooth to the touch. He sanded the wood down until it was as smooth as glass.
See also: glass, smooth
Farlex Dictionary of Idioms.

*smooth as glass

 and *smooth as silk
Cliché smooth and shiny. (often used to describe calm bodies of water. *Also: as ~.) The bay is as smooth as glass, so we should have a pleasant boat trip. This custard is smooth as silk.
See also: glass, smooth
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • (as) smooth as glass
  • not have a ghost of a chance
  • not have a/the ghost of a chance
  • not have the ghost of a chance
  • not lay a finger on (someone or something)
  • not lay a finger on someone
  • not care/give a damn
  • not give a damn
  • a rod/stick to beat somebody with
  • a stick to beat someone with
References in classic literature
As you look over the pond westward you are obliged to employ both your hands to defend your eyes against the reflected as well as the true sun, for they are equally bright; and if, between the two, you survey its surface critically, it is literally as smooth as glass, except where the skater insects, at equal intervals scattered over its whole extent, by their motions in the sun produce the finest imaginable sparkle on it, or, perchance, a duck plumes itself, or, as I have said, a swallow skims so low as to touch it.
Walden & on the Duty of Civil Disobedience
in quiet, when the surface is again as smooth as glass,
Tallahatchie