pso·cid 
(sōsĭd, sŏsĭd)
(sōsĭd, sŏsĭd)n.
Any of various small soft-bodied chewing insects of the order Psocoptera, which includes the booklice. The psocids are sometimes classified together with the parasitic lice in the order Psocodea.
[From New Latin Psōcidae, family name, from Psōcus, type genus, from Greek psōkhos, dust.]