outgrowth vs appendage

outgrowth and appendage both are nouns.

Word	Noun	Adjective	Verb	Adverb
outgrowth	Yes	No	No	No
appendage	Yes	No	No	No

As nouns, outgrowth and appendage are synonyms defined as:

outgrowth and appendage: a natural prolongation or projection from a part of an organism either animal or plant

Other synonyms of outgrowth include process.

outgrowth (noun)	appendage (noun)
a natural prolongation or projection from a part of an organism either animal or plant	a part that is joined to something larger
the gradual beginning or coming forth	an external body part that projects from the body
a natural consequence of development	a natural prolongation or projection from a part of an organism either animal or plant