oak fern
noun
1- a delicate fern of woods and damp places in the uplands of northern Eurasia and North America羽节蕨。
1.1
- Genus Gymnocarpium (formerly Thelypteris), family Woodsiaceae: two species, in particular G. dryopteris.羽节蕨属（原沼泽蕨属）, 岩蕨科：2种, 尤指欧洲羽节蕨。