A plant characterized by wood, bark and pith, the wood forming a layer between the other two, and growth only occurring on the outside.(noun)
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Use "exogen" in a sentence
"Smilax belongs to a transition class, partaking somewhat of the nature of endogen and of exogen."
"The former sees a tree in all its glory, where the latter sees an exogen with a pair of cotyledons."
"Standardmetoden i forskningen är att hitta någon exogen källa till variation i mängden bistånd som olika länder får: Ett så kallat instrument för bistånd."