Synonyms for Outgrowth (same or very similar meaning)
WordNet sense 1 (a natural consequence of development):
branch, offset, offshoot
WordNet sense 2 (the gradual beginning or coming forth):
emergence, growth
WordNet sense 3 (a natural prolongation or projection from a part of an organism either animal or plant):
appendage, process, process
From the ODE community, based on WordNet
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