[f. TANGLE sb.1 + -Y.] Strewn with, full of, or consisting of tangle.

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1762–9.  Falconer, Shipwr., III. 777. Helpless, on the tangly beach he lay.

2

a. 1851.  Moir, Old Seaport, iii. Far beneath the surf upheaved The sea-weed’s tangly arms.

3