amniocentesis

the term is a modern medical neologism, constructed in the 20th century by directly combining two greek-derived elements. 'amnion' originates from the greek word for a lamb, later used for the fetal membrane, perhaps due to its association with the caul (the inner membrane) sometimes found on newborn lambs. 'centesis' derives from the greek 'kentein', meaning to prick or pierce, a root also seen in words like 'acupuncture'. the compound word 'amniocentesis' thus follows a transparent, descriptive logic common in scientific terminology, literally meaning "the puncture of the amnion" to describe the surgical extraction of amniotic fluid for diagnostic purposes.

Structure: amnio (amnion) + centesis (puncture) amnio: from greek 'amnion', meaning the membrane around a fetus. in this word, it functions as a combining form referring to the amniotic sac. centesis: from greek 'kentēsis', meaning the act of pricking or puncturing. in this word, it functions as a suffix denoting a surgical puncture procedure.