Word Study
exogen
CIDE DICTIONARY
exogen, n. [Exo- + -gen: cf. F. exogène.].
A plant belonging to one of the greater part of the vegetable kingdom, and which the plants are characterized by having c wood bark, and pith, the wood forming a layer between the other two, and increasing, if at all, by the animal addition of a new layer to the outside next to the bark. The leaves are commonly netted-veined, and the number of cotyledons is two, or, very rarely, several in a whorl. Cf. Endogen. Gray. [1913 Webster]
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