white cell vs free phagocyte

white cell and free phagocyte both are nouns.

Word	Noun	Adjective	Verb	Adverb
white cell	Yes	No	No	No
free phagocyte	Yes	No	No	No

As nouns, free phagocyte is a hypernym of white cell; that is, free phagocyte is a word with a broader meaning than white cell:

white cell: blood cells that engulf and digest bacteria and fungi; an important part of the body's defense system
free phagocyte: a phagocyte that circulates in the blood

Other hypernyms of white cell include blood cell, blood corpuscle, corpuscle.

white cell (noun)	free phagocyte (noun)
blood cells that engulf and digest bacteria and fungi; an important part of the body's defense system	a phagocyte that circulates in the blood