-plasia

1712, "form, shape" (a sense now obsolete), a more classical form of earlier plasm; from Late Latin plasma, from Greek plasma "something molded or created," hence "image, figure; counterfeit, forgery; formed style, affectation," from plassein "to mold," originally "to spread thin," from PIE *plath-yein, from root *pele- (2) "flat; to spread."

Sense of "the liquid part of blood, etc., as distinguished from the corpuscles" is from 1845. In physics, the sense of "ionized gas" is by 1928.

"defective or arrested development of a body part," 1876, medical Latin, from Greek a- "not, without" (see a- (3)) + -plasia "formation, growth, development." Related: Aplastic.