frost over/up phrasal verbphr v COLDto become covered in frost 布满霜,结霜 Overnight all the windowpanes had frosted over. 一夜之间,窗玻璃上都结满了霜。
frost over/up• Overnight all the windowpanes had been frosted over.• All the windowpanes had frosted over during the night.
→ frost over/up at frost2(1)