What is "laminaria digitata"

Sea girdles \Sea" gir"dles\ (Bot.) A kind of kelp ( Laminaria digitata) with palmately cleft fronds; -- called also sea wand, seaware, and tangle.

Laminaria digitata is a large brown alga in the family Laminariaceae, also known by the common name Oarweed. It is found in the sublittoral zone of the northern Atlantic Ocean.