Diphyllobothrium
noun
Di·phyl·lo·both·ri·um
| \ -ˈbäth-rē-əm
\
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Medical Definition of Diphyllobothrium
: a large genus of tapeworms that is the type genus of the family Diphyllobothriidae and that comprises a number of parasites of fish-eating birds and mammals including the fish tapeworm (D. latum) of humans — compare bothriocephalus