Late Middle English; earliest use found in Guy de Chauliac's Grande Chirurgie. From post-classical and scientific Latin cellulatus composed of or containing cells from classical Latin cellula + -ātus.
cellulate2
/ˈsɛljʊleɪt/
verb
1[with object]To supply with cells; to make cellular; to divide into cells.
2[no object]To become cellular.
Origin
Mid 19th century; earliest use found in Todd's Cyclopaedia of Anatomy and Physiology. From cellule + -ate, after cellulated.