deesis Save Gaffiot 2016 Du Cange dĕēsis, is, f. (δέησις), prière, invocation [rhét.]: Rufinian. Schem. dian. 16. DEESIS. Deesis, obsecratio, vel obtestatio, qua Deos oramus, aut homines. Cic. (Dejot. 3.) Per dexteram istam tuam ego obtestor, etc.