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sea oat

noun

Definition of sea oat 

1 : a tall grass (Uniola paniculata) that has panicles resembling those of the oat, grows on the coast of the southern U.S., and is useful as a sand binder —usually used in plural

2 sea oats plural : a cluster of yellowish vase-shaped egg cases of a whelk of the genus Thais : sea corn

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First Known Use of sea oat

1879, in the meaning defined at sense 1

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The first known use of sea oat was in 1879

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