frosten

verb

1. (ambitransitive)To make or become frosted

   “Her appearance was extremely neat. Her dark brown hair laid neatly upon either side of a high fair brow — and Time had kindly refused to frosten one single thread of it.”

   “The sky was cloudless; the foliage of the wood scarce tinged with purple and gold; the buckwheat in yonder fields frostened into snowy ripeness.”