excrescent (adj) – growing out of something else, usually exhibiting abnormal growth; superfluous
BREAKDOWN: EX- (out) + CRE- (grow) + -ENT (tending to)
— an excrescence is a growth or disfiguring mark
This word is built on the root CRE-, which means to grow or increase.
Common CRE- words include crescent, crew, decrease, or increase.
More esoteric CRE- words include accretive and decremental.