A brown alga, Laminaria digitata, found on exposed shores (noun)
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Use "oarweed" in a sentence
"As I lay flat on the rock to drop my nets, the rattle and roar of the sea beyond, vibrating through the solid stone, the whistle of the wind through the downhanging oarweed, sounded like an orchestra of the mad damn'd."
"Broad-leaved oarweed covered it like giant hair, and hung drooping into the deep black pool beneath."
"So the rocks were uncovered now, which seldom tasted the air, and the stems of the great oarweed, or tangle, which grew from them, were bent into a half-circle by the weight of their broad leathery fronds, as, no longer buoyed up by the sea, they lay trailing on the sands."