noun

• (anatomy, zootomy) A flexible enclosing or separating tissue forming a plane or film and separating two environments.
• A mechanical, thin, flat flexible part that can deform or vibrate when excited by an external force.
• A flexible or semiflexible covering or waterproofing whose primary function is to exclude water.
• (biology) A microscopic double layer of lipids and proteins forming the boundary of cells or organelles.
• A piece of parchment forming part of a roll.