sea oat

noun

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

Word History

First Known Use

1879, in the meaning defined at sense 1

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