monolayer

Etymology

mono- + layer

noun

1. (chemistry) A layer of material that is one molecule thick
   Recently a stable monolayer of antimony in buckled honeycomb structure called antimonene was successfully grown on 3D topological insulator Bi₂Te₃ and Sb₂Te₃, which displays semiconducting properties. 2016, Yuanfeng Xu, Bo Peng, Hao Zhang, Hezhu Shao, Rongjun Zhang, Hongliang Lu, David Wei Zhang, Heyuan Zhu, “First-principle calculations of phononic, electronic and optical properties of monolayer arsenene and antimonene allotropes”, in arXiv
2. (biology) A layer of tissue that is one cell thick