lymphedema vs dropsy

lymphedema and dropsy both are nouns.

Word	Noun	Adjective	Verb	Adverb
lymphedema	Yes	No	No	No
dropsy	Yes	No	No	No

As nouns, dropsy is a hypernym of lymphedema; that is, dropsy is a word with a broader meaning than lymphedema:

lymphedema: swelling (usually in the legs) caused by lymph accumulating in the tissues in the affected areas
dropsy: swelling from excessive accumulation of watery fluid in cells, tissues, or serous cavities

Other hypernyms of lymphedema include edema, hydrops, oedema.

lymphedema (noun)	dropsy (noun)
swelling (usually in the legs) caused by lymph accumulating in the tissues in the affected areas	swelling from excessive accumulation of watery fluid in cells, tissues, or serous cavities