lochia vs body fluid

lochia and body fluid both are nouns.

Word	Noun	Adjective	Verb	Adverb
lochia	Yes	No	No	No
body fluid	Yes	No	No	No

As nouns, body fluid is a hypernym of lochia; that is, body fluid is a word with a broader meaning than lochia:

lochia: substance discharged from the vagina (cellular debris and mucus and blood) that gradually decreases in amount during the weeks following childbirth
body fluid: the liquid parts of the body

Other hypernyms of lochia include bodily fluid, humor, humour, liquid body substance.

lochia (noun)	body fluid (noun)
substance discharged from the vagina (cellular debris and mucus and blood) that gradually decreases in amount during the weeks following childbirth	the liquid parts of the body