Its specific epithet filix-mas means "male fern (filix "fern", mas "male")", as the plant was thought to be the male version of the female fern, being robust in appearance and vigorous in growth.
The semi-evergreen leaves have an upright habit and reach a maximum length of 150 cm (59 in), with a single crown on each rootstock. The bipinnate leaves consist of 20-35 pinnae on each side of the rachis. The leaves taper at both ends, with the basal pinnae about half the length of the middle pinnae. The pinules are rather blunt and equally lobed all around. The stalks are covered with orange-brown scales. On the abaxial surface of the mature blade 5 to 6 sori develop in two rows. When the spores ripen in August to November, the indusium starts to shrivel, leading to the release of the spores.