Mozuku (Nemacystus decipiens) is marine alga classified under the family Spermatochnaceae or the family Chordariaceae in the order Chordariales, the class Phaeophyceae.
モズク（水雲、海蘊）は、褐藻綱・ナガマツモ目のうち、モズク科やナガマツモ科に属する海藻の総称。