Peptidoglycan

Etymology
Peptidoglycan:

peptide, a chain of amino acids: "cooked" (from greek πεπτός (peptos), meaning "cooked" or "digested", referring to the protein-containing broth used in cultures that was created by cooking/digesting meat)

glycan, a polysaccharide: "sweet" (from greek γλυκύς (glycos), meaning "sweet", since polysaccharides are sugars which taste sweet)

Explanation
Peptidoglycan is a large polymer which is comprised of amino acid chains (peptides) and polysaccharides (glycans), that makes up the bacterial cell wall.

Synonyms
Murein