monocyte vs leukocyte

monocyte and leukocyte both are nouns.

Word	Noun	Adjective	Verb	Adverb
monocyte	Yes	No	No	No
leukocyte	Yes	No	No	No

As nouns, leukocyte is a hypernym of monocyte; that is, leukocyte is a word with a broader meaning than monocyte:

monocyte: a type of granular leukocyte that functions in the ingestion of bacteria
leukocyte: blood cells that engulf and digest bacteria and fungi; an important part of the body's defense system

Other hypernyms of monocyte include leucocyte, WBC, white blood cell, white blood corpuscle, white cell, white corpuscle.

monocyte (noun)	leukocyte (noun)
a type of granular leukocyte that functions in the ingestion of bacteria	blood cells that engulf and digest bacteria and fungi; an important part of the body's defense system