integument

Etymology

Borrowed from Latin integumentum (“a covering”).

noun

1. A shell or other outer protective layer.
   […] if we're moved by the book's condemnation of a world wounded by exploitation, where the drive for profit hobbles the mass of humanity, bolsters vast integuments of oppression and repression, […] 2022, China Miéville, chapter 6, in A Spectre, Haunting: On the Communist Manifesto, →OCLC
2. (biology) An outer protective covering such as the feathers or skin of an animal, a rind or shell.
   Sarsem became a naked young epicene in an integument of lavender scales with puffs of purple hair like pom-poms growing down his back. 1984, Jack Vance, Rhialto the Marvellous
3. (botany) The outer layer of an ovule, which develops into the seed coat.
   Her active living was suspended, but underneath, in the darkness, something was coming to pass. If only she could break through the last integuments! 1920, D.H. Lawrence, chapter 1, in Women in Love