posh I. \ˈpäsh\noun (-s) Etymology: imitative of the sound made by walking through slush archaic: a slushy mass (as of mud or broken ice) < posh and ice in the river — Walt Whitman > II. adjective Etymology: origin unknown 1.: smart or spruce in appearance 2.: elegant or luxurious in an extreme degree < a posh finishing school > III. interjection — used to express disdain or contempt