parenchyma

From Ancient Greek παρέγχῠμα (parénkhŭma, “anything poured in beside”), from πᾰρᾰ- (pără-, “beside”) +‎ ἔγχῠμα (énkhŭma, “instillation, content of a vessel”), given by the Greek anatomist Erasistratus to the peculiar substance of the lungs, liver, kidneys, and spleen, as if formed separately by the veins that run into them. By surface analysis, para- +‎ -enchyma.