Definition of knotted wrack in English:

knotted wrack

Line breaks: knot|ted wrack

noun

[mass noun]
  • A dark olive-green seaweed with flat branching fronds which bear air bladders, occurring on rocky seashores.
    • Ascophyllum nodosum, class Phaeophyceae
    More example sentences
    • Its eggs are laid in May and June, primarily on rock surfaces that, at low tide, are covered with the knotted wrack Ascophyllum nodosum.

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Pronunciation: ˌastrəˈgāSHən
noun
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