meromelia vs phocomelia

meromelia and phocomelia both are nouns.

Word	Noun	Adjective	Verb	Adverb
meromelia	Yes	No	No	No
phocomelia	Yes	No	No	No

As nouns, phocomelia is a hyponym of meromelia; that is, phocomelia is a word with a more specific, narrower meaning than meromelia:

meromelia: congenital absence of part of an arm or leg
phocomelia: an abnormality of development in which the upper part of an arm or leg is missing so the hands or feet are attached to the body like stumps; rare condition that results from taking thalidomide during pregnancy

Other hyponyms of meromelia include adactylia, adactylism, adactyly, seal limbs.

meromelia (noun)	phocomelia (noun)
congenital absence of part of an arm or leg	an abnormality of development in which the upper part of an arm or leg is missing so the hands or feet are attached to the body like stumps; rare condition that results from taking thalidomide during pregnancy