Not wrinkled or creased.

synoniem: wrinkleless.

Roget 255: smooth; polished etc. v.; leiodermatous^†, slick, velutinous^†; even; level etc. 213; plane etc. (flat) 251; sleek, glossy; silken, silky; lanate^†, downy, velvety; glabrous, slippery, glassy, lubricous, oily, soft, unwrinkled^†; smooth as glass, smooth as ice, smooth as monumental alabaster, smooth as velvet, smooth as oil; slippery as an eel; woolly etc. (feathery) 256.    ... meer laten zien