appendage vs outgrowth

appendage and outgrowth both are nouns.

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

As nouns, appendage and outgrowth are synonyms defined as:

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

Other synonyms of appendage include process.

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