leucopenia vs leukopenia

leucopenia and leukopenia both are nouns.

Word	Noun	Adjective	Verb	Adverb
leucopenia	Yes	No	No	No
leukopenia	Yes	No	No	No

As nouns, leucopenia and leukopenia are synonyms defined as:

leucopenia and leukopenia: an abnormal lowering of the white blood cell count

leucopenia (noun)	leukopenia (noun)
an abnormal lowering of the white blood cell count	an abnormal lowering of the white blood cell count