Meaning of hat plant in English:
hat plant
noun
1(Originally) any of various plants, the pith or leaf fibres of which are used to make hats and other woven objects, especially the rice paper plant, Aeschynomene aspera (now rare).
2(In later use) any of various plants, the flowers, foliage, etc., of which are thought to resemble a particular type of hat.
Origin
Late 19th century.
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