cold frame
noun [ C ] uk/ˈkəʊld ˌfreɪm/ us/ˈkoʊld ˌfreɪm/
（用来保护秧苗的）冷床，阴畦
a glass or plastic box, with a top that can be left open, into which young plants are put for a short time, especially in order to help them grow faster or to protect them from cold weather