bothridium

bothridium (noun; plural bothridia; Greek diminutive bothros, trench): 1. (Arthropoda: Chelicerata) A chitinous cavity or projecting cup in which a bothridial seta is inserted; (bothridial seta + bothridium = trichobothrium).

2. (Platyhelminthes: Cestoda) One of 4 muscular lappets on the scolex of a tapeworm, often highly specialized with many types of adaptations for adhesion.