Docetism

Concise Oxford English Dictionary © 2008 Oxford University Press:
Docetism /dəˈsiːtɪz(ə)m, ˈdəʊsɪˌtɪz(ə)m/

▶noun the doctrine that Christ's body was not human (being either a phantasm or of real but celestial substance) and that therefore his sufferings were only apparent.

– derivatives
Docetist noun.

– origin C19: from med. L. Docetae (the name, based on Gk dokein ‘seem’, given to a group of 2nd-cent. Christian heretics) + -ism.