柯林斯词典fern /fɜːn/ (ferns) 1. N-VAR A fern is a plant that has long stems with feathery leaves and no flowers. There are many types of fern. 蕨类植物 返回 fern剑桥词典a green plant with long stems , leaves like feathers , and no flowers 蕨；蕨类植物 返回 fern