Tegmen
Tegmen , noun
[Latin, from tegere, tectum, to cover.]
1.
A tegument or covering.
2.
(Botany) The inner layer of the coating of a seed, usually thin and delicate; the endopleura.
3.
(Zoology) One of the elytra of an insect, especially of certain Orthoptera.
4.
(Zoology) Same as Tectrices.