Definition of Parenchyma

Parenchyma: The key elements of an organ essential to its functioning, as distinct from the capsule that encompasses it and other supporting structures. The parenchyma is thus opposed to the connective tissue framework, or stroma, of an organ. The parenchyma of the testis consists of what are called the seminiferous tubules.

The Greek word "parenchyma" means "that which is poured in." It reflects the ancient (and erroneous) idea that the inner substance of solid organs like the liver, spleen and kidneys was formed by blood that was poured into it.

The word is pronounced "pa-ren-ki-ma" with the "y" in "parenchyma" pronounced as a short "i" rather than as "eye."