What is a genus of leguminous herbs with densely spiked flowers and usually trifoliate leaves; trefoil. There are many species, all of which are called clover. See Clover called?

trifolium — A genus of leguminous herbs with densely spiked flowers and usually trifoliate leaves; trefoil. There are many species, all of which are called clover. See Clover. (Webster's 1913.)

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