epicoelian
/ˌɛpɪkɔːˈliən/Definitions
1. adjective
relating to or resembling an epicoel, especially in the structure of a cell wall
“The epicoelian layer of the cell wall provided added protection against external stress.”
2. noun
the outermost layer of the cell wall in certain algae, composed of a rigid polysaccharide
“The epicoelian layer was responsible for the algae’s ability to withstand strong water currents.”