bdellium
-an unidentified substance mentioned in the bible (gen. ii. 12, and num. xi. 7), variously taken to be a gum, a precious stone, or pearls, or perhaps a kind of amber found in arabia.
-a gum resin of reddish brown color, brought from india, persia, and africa.

bdelloidea
-the order of annulata which includes the leeches. see hirudinea.

bdellometer
-a cupping glass to which are attached a scarificator and an exhausting syringe.

bdellomorpha
-an order of nemertina, including the large leechlike worms (malacobdella) often parasitic in clams.