Literally meaning: "the eating of cells"
Origin: Anc Greek
φάγος/phagos(=eater) > έφαγον/ephagon(=indefinite tense of verb "εσθίω"/esthio(eat, devour)
+cyte(=combining form meaning “cell” derived from anc Greek word κυτίον/cytion (=box, container)
=-ωσις/-osis(=suffix denoting usually a procces )
In 1882 by Russian zoologist Ilya Ilyich Mechnikov (1845-1916) described the specialized cells that were involved in the defense against microbial infections and after sharing his findings with Carl Friedrich Claus (Vienna) he named them "phagocytes". Mechnikov, a year later added the term "phagocytosis" concerning all the procces of engulfing pathogens by these cells.
Phagocytosis is the cellular process which is used by cells of immune system in order to engulf and indigest solid particles as microorganisms and cellular debris.