The Great Soviet Organoid

 Warning! The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Endoplasmic Reticulum   

in biology, an intracellular organoid that consists of a system of flat cisternae, tubules, and vesicles that are bounded by membranes. Its main function is to ensure the transfer of matter from the surrounding medium into the cytoplasm and between intracellular structures. The endoplasmic reticulum was discovered with an electron microscope in 1945 by K. Porter and other American scientists. It is usually located in the cytoplasm immediately surrounding the nucleus (the endoplasm) in all the cells, except the erythrocytes, of eukaryotes.

Nice try comrade, but we call it an organelle now.

(Source: encyclopedia2.thefreedictionary.com)