Ruppa in ruppa-rūpakaṃ (neuter) Thig 394 is not clear. It refers to something which is not rūpa, yet pretends to be rūpa, i.e. a sham performance or show. Thus ruppa may correspond to *rūpya and with rūpaka mean "having the form (i.e. the appearance) of form, i.e. substantiality." The commentary (Thig-a 259) interprets as "rūpiya-rūpasadisaṃ sāraṃ sāraṃ upaṭṭhahantaṃ asāran ti attho"; and Mrs. Rh.D. ( Ps.S. , page 154) translates: "deluded by puppet shows (seen in the midst of the crowd)."
(adj, adj, from rūpa) beautiful; attractive; well-formed; (comm) silver Construction: √rūp + a + ya rūpa + ya